Boris Johnson expects everybody to go "above and beyond" in following Covid rules, his spokeswoman has said after Conservative Welsh politicians were seen drinking during a pub alcohol ban.
Senedd Tory leader Paul Davies, Darren Millar and Labour's Alun Davies have apologised for drinking in the Welsh Parliament days after the ban started.
They are not thought to have broken the rules, but the two Tories admitted it would not be seen as in their spirit.
Senedd authorities are investigating.
A fourth Senedd Member Nick Ramsay has denied being part of the gathering.
On 8 December, a group of Members of the Senedd and staff drank alcohol in the Ty Hywel building in Cardiff Bay, which houses the Senedd's offices.
A ban on the sale, supply and consumption of alcohol in licensed premises came into force in Wales at 18:00 GMT on 4 December - four days before the politicians were seen drinking together - although hospitality businesses could sell alcohol to take away after 18:00.
Catering company Charlton House has the licence for serving alcohol on Senedd premises.
The Welsh Government stated on Tuesday that the alcohol ban applied to the person running the licensed premises, rather than customers.
'No matter their position'
Speaking at a journalists' lobby briefing Allegra Stratton, Boris Johnson's press secretary, said she had not spoken to the prime minister about whether Welsh Conservative Senedd leader Paul Davies should remain in post.
But she added: "The prime minister needs everybody - no matter their status, no matter their position in life - to be going above and beyond in following the rules on Covid."
The former chairman of a Westminster standards watchdog questioned whether the three involved should be put up for election at the next Welsh Parliament polls on 6 May.
Sir Alistair Graham, the former chairman of the Committee on Standards in Public Life, said if the allegations were proven "then both parties are bound to ask questions" ahead of the election.
"Do they want such people, who have shown such a lack of leadership, standing for election?," he said.
He told BBC Radio Wales: "I think it's very serious, poor behaviour by a group of politicians who we expect to give a lead about the spirit of the rules never mind the precise detail."
He said the action by the Labour Party - to suspend Alun Davies - was appropriate and the Conservatives "should have done the same".
Mr Ramsay was deselected by his local Conservative group last month after 13 years.
A statement from his solicitor, Tim Gir, said Mr Ramsay was at the tea room on his own at the Senedd, without an invitation from anyone else, after work.
"He was hungry and he wanted to get something to eat. He was working on an article for the Argus [newspaper]. He sat on his own and was socially distanced," said Mr Gir.
"He attended the tea room at approximately 6pm. He had a chicken curry. He left at about 8pm. Others came in whilst he was there but it was not a 'gathering' Mr Ramsay was part of."
On Wednesday afternoon the health minister said the "last thing" that should happen at the end of an investigation was that "it's only staff who essentially get thrown under the bus, everyone needs to look what they've done".
At a press conference, Vaughan Gething refused to be drawn on whether the Tory members should stand down or be suspended.
But he said the Labour group's decision to suspend Alun Davies "was the right thing" to do.
He said he himself had been subject of press stories "where some people made comments, without wanting to understand the facts or not being interested in them so I don't think I should then lay in on an issue like this".
But, he added: "Any sense of people not all being in this together, isn't helpful in terms of the message that we all need to follow."
A senior Conservative source has told BBC Wales they were "totally flabbergasted" that the party Senedd members involved have not stood down pending the investigation.
"There's a lot of anger and I don't know how they can continue," the source added.
"Everyone I've spoken to in the party is just completely baffled by this.
"This is a complete own goal."
Covid: Politicians drank at Senedd despite alcohol ban. Disgraceful behaviour from the people who are supposed to leading us through the pandemic. They should stand aside and go @WelshConserv @NewportTories . Another good reason to abolish https://t.co/gHnn2Y0cvg— David Fouweather (@DaveFouweather) January 19, 2021
David Fouweather, a Conservative councillor in Newport, said the Tories involved should "stand aside and go".
One senior Conservative grassroots official who contacted BBC Wales said: "I'm furious. The party messaging is trying to break up the Cardiff Bay cartel and they're having nice drinks with Alun Davies who, let's not forget, has been really vicious in public against us.
"I've spoken to a lot of Conservatives and they're not happy at all.
"Nobody is going to put their head on the line for Paul Davies. I'll be very surprised if he continues to the end of the week."
The official also referred to Mr Millar's call at the start of the pandemic for the first minister to sack Health Minister Vaughan Gething over claims he broke Covid rules at the time when he sat and ate chips while on a walk with his family.
The grassroots activist said: "Darren Millar talking about Vaughan Gething having his chips - well, what on earth is he doing?"
Another Conservative councillor said: "Paul's position as leader is now untenable, especially when you consider the strain that hardworking people are under."
A senior Welsh Government minister also joined calls for the Conservative Party to take action of its own.
Eluned Morgan, mental health minister, said she had written to the party asking it suspend those involved while "investigations continue into this alleged incident".
Labour has suspended Alun Davies from the party's Senedd group pending an investigation.
Plaid Cymru MS Rhun ap Iorwerth said politicians failed to set "the best example that's something that should be regretted by all of us".
"I want to be talking about how we can push government to deliver better in its response to this pandemic," he said.
"It's a matter of concern to me that distractions like this move the focus from where it should be and where you then have questions about the role of political leaders - and I count all of us, whether in government or in opposition, in that bracket."
Licensee 'aware of alleged breach'
Charlton House said it was "aware of an alleged breach of public health regulations at the Senedd estate" and took its "responsibilities and obligations to restrictions and public health regulations across the UK very seriously".
"We are currently undertaking a full investigation into this matter," the firm added.
Wales' chief medical officer Dr Frank Atherton said it was "important that everybody follows the rules".
"I don't know the details of what may or may not have happened down there, I'm sure that will come out in the fullness of time," he told BBC Wales Live on Tuesday.
What do the politicians involved say?
A statement on behalf of Paul Davies, Darren Millar and Welsh Conservative chief of staff Paul Smith, who was also at the meeting, said they were "profoundly sorry".
"While we did not break the rules, we recognise that what was part of a day's work would not be seen to be following the spirit of them, especially given the tough time the country has been going through," the statement said.
A spokesman for the Senedd Labour Group said a member had been suspended from the group "while an investigation takes place into this alleged incident".
In his statement, Labour's Alun Davies said: "I am very sorry if my actions have given the impression that I am in any way not committed to upholding the regulations which I have consistently supported throughout the last year."
He said the purpose of the meeting "was to seek to persuade the Welsh Conservatives to support my proposal for a Welsh Hearts Bill, which the Senedd endorsed on 21 October, and to make a commitment to enact this life-saving legislation in their manifesto for May's election".
Alun Davies added: "The Senedd Commission has already confirmed to me that I did not breach the coronavirus regulations on the consumption of either food or alcohol that were in force at that time."
A spokesman for the Senedd Commission said: "We are aware of an incident on the Senedd estate last month which may have been contrary to public health regulations in force at the time.
"The Senedd Commission takes the public health regulations in Wales very seriously and is currently investigating the matter in order to establish an accurate account of what took place and to determine whether action may be required."