Reopening pubs too soon could run the risk of "undoing all the good" during lockdown, an infectious disease expert has said.
Beer gardens reopened in England on Monday, but in Wales industry experts have expressed frustration they cannot open until 26 April.
Dr Mike Tildesley said it was important lockdown was eased gradually to stop a spike in coronavirus cases.
The Welsh government said it was taking "a careful step-by-step approach".
Dr Tildesley, who is part of a modelling group which advises the UK government on the pandemic, said he understood people were "frustrated" at the different timetables out of lockdown.
However, he said a cautious approach was needed for the next few weeks to prevent a third wave, in the hope "we can get back to normal by summer".
"We need to remember that these are paced at a rate that the vaccinations can keep up with us and can help us along the way," he told BBC Radio Wales.
More than half the people in Wales have now had their first Covid-19 vaccination dose, and Covid admissions to hospitals in Wales have hit record low levels.
Dr Tildesley said while things were moving in the right direction, scientists needed to monitor the impact of relaxing other restrictions on case rates, before reopening other parts of life.
On Monday shoppers queued as non-essential shops reopened in Wales for the first time since they were forced to close in the run-up to Christmas.
"The key thing is we need to take it at a gradual rate so we can ensure that we can reopen safely... we are doing well, but if we go too fast we run the risk of too much mixing, and undoing all the good we have done so far," he said.
While he said cases could go up as people began mixing again and going back to their daily lives, the progress of the vaccine should help avoid a "significant resurgence".
Dr Tildesley urged people to be cautious for a few more weeks, adding the biggest concern was that if there was a spoke in cases the virus could mutate.
"We are not quite out of the woods yet, in the not too distant future we will be in a position where we can meet people... and hug our friends and family again, but we are not there yet," he said.
'Always two weeks behind'
One landlord, whose pub is on the border said it was "frustrating" remaining closed until 26 April when outdoor hospitality opened on Monday in England.
John Turner said two other pubs in his village - that are technically in England - had now reopened.
But Mr Turner, who runs the Dolphin Inn, in Llanymynech, on the Powys-Shropshire border, said Wales was "always two weeks behind England" and he was anxious to open again.
On Monday, the border reopened between Wales and England and people are now allowed to travel in both directions.
Once in England, you can visit a pub or cafe garden with up to six people from individual households, or any number from two households.
'Slow and cautious is better'
However, some people have agreed with Dr Tildesley's view and expressed relief pubs remain closed in Wales.
Garfield Doc Oakleeffe posted on Facebook: "After seeing the footage of the lack of social distancing when drinking in Soho, I think slow and cautious is better."
Sian Louise said: "I know it's horrible to not be open and I feel for businesses, I really do as I was getting annoyed with it all, but by looking how this last lockdown went and how it started I actually understand why [Mark Drakeford is] doing it slowly, because we don't want another lockdown and we don't want anymore people getting seriously ill either.
"Hopefully, in time we will come out better and safer by doing it gradually."
Michelle Murphy commented: "I am so glad they are still closed. If this is what it is going to be like, no wonder they predict a third wave."
Kerry Lea Edwards did not understand the "urgency to be back in the pub", adding: "If it's the social side you can meet outdoors in your garden with your friends and have a drink.
"Surely it's not worth the risk - we will be in another lockdown before we know it, very sad."
'Is it safe? I think it is'
Mr Turner said: "The firebreak [lockdown] was going to be the saviour for Christmas and then I didn't even imagine we would miss out on Easter as well.
"An extra two weeks' trade will be lost once again to England."
He added that even when pubs in Wales can reopen, it could be a struggle only being able to serve outside because of "the weather element".
While he has used some of his government support to put up a marquee, and purchase heaters and furniture, he said other pubs might not be able to keep up.
He said he was anxious to make the money back to make the new equipment worthwhile.
"People are desperate to get to the pub. I am hopeful we will be full and I'm looking forward to being busy again because otherwise it will be harder and more disappointing," he said.
'A bitter pill to swallow'
Emma McClarkin, chief executive of the Welsh Beer and Pub Association (WBPA), said pubs across Wales were "hugely disappointed" to not open on Monday alongside England.
She said pubs in Wales having to wait another two weeks while pubs in England were trading outdoors was "a bitter pill to swallow".
Ms McClarkin said: "Vaccination rates continue to climb while case rates are falling week on week. Even when they will be allowed to open, we still think about 60% of pubs in Wales will be unable to because of a lack of usable outside space.
"The Welsh government need to recognise that and bring forward a package of funding as soon as possible that will prevent hundreds of Welsh pubs being lost for good."
The Welsh government said it had provided more than £2bn of funding to support businesses impacted by the pandemic, safeguarding 165,000 Welsh jobs.
A spokesperson said tourism and hospitality businesses would continue to receive cash grants this month to help them through until the reopening date in May.
"Businesses will therefore see no interruption in the flow of financial support, as we move cautiously to relax public health restrictions," they said.
"Another £200m in additional support for business has already been earmarked in the Final Budget 2021-22.
"Ministers have had a constructive meeting with representatives from the hospitality sector and Welsh government officials will work with them on options for a further support package to be put to the new government following May's Senedd election."
What is the political reaction?
A Plaid Cymru spokesperson said many would question the decision not to move forward the reopening of beer gardens after scenes like those seen in Cardiff Bay, where crowds gathered to drink over the bank holiday weekend.
"A regulated drinking environment is, after all, a better and safer option," the spokesperson said.
"Likewise, the lack of clear date on indoor hospitality remains a major problem and at the very least the government should urgently revisit its decision to delay any additional financial support until after election."
Leader of the Welsh Conservative group Andrew RT Davies, said the Welsh government's decision was about politics not science, and lost trade meant "lost livelihoods in Wales".
"After a crippling 12 months for businesses, Labour ministers in Cardiff Bay seem to have a tin ear to these concerns. Welsh Conservatives would cut the border games, end the confusion, and get Wales on the road to recovery with a safe, consistent and one-nation approach," he said.
The Welsh Liberal Democrats said: "Lockdown is frustrating but we all need to stay safe and follow the regulations.
"If we do, we will not need to enter a lockdown again and that is the the most important thing. We've seen before what happened when lockdowns were eased too quickly."