Welsh Labour would be "entirely open" to introducing an official register of lobbyists if the party wins the Senedd election, the health minister said.
Vaughan Gething made the pledge during a BBC Radio 4 debate, during which Plaid Cymru's Delyth Jewell said she backed an official register.
Conservative Senedd leader Andrew RT Davies said lobbying needed to be addressed across all parliaments.
The Welsh Liberal Democrats' Jane Dodds said "more transparency" was needed.
Hosted by BBC political correspondent Chris Mason in Cardiff, Radio 4's Any Questions debate was held amid a row over former prime minister David Cameron's contacts with senior UK government ministers on the behalf of the finance company Greensill Capital.
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Unlike in Westminster and the Scottish Parliament, lobbyists in Wales do not have to sign an official register.
A 2018 report by the standards committee in Cardiff Bay found little evidence to support a voluntary register, but recommended waiting to see how the forthcoming Scottish system works before taking a decision in Wales.
Lord Pickles, who chairs the body that advises former ministers and civil servants on outside employment, has said the rules on ministers and top officials taking jobs with private firms need urgent reform.
Asked about the scandal, Andrew RT Davies called on all politicians in the UK to "heed" Lord Pickles' words and respond to any inquiries "positively".
"I think it is important to reflect that sadly, there have been incidences in Wales," he said.
"So, we need to be looking across all the parliaments and assemblies of the United Kingdom to make sure that this is addressed."
Mr Davies referred to former first minister Carwyn Jones, who was accused of breaking the rules that regulate ex-ministers taking up new jobs.
Appointed to the board of GFG Alliance, which owns Newport's Liberty Steel, Mr Jones had been warned against advising on steel and was accused of breaching the ministerial code.
The former first minister insisted he had not done "anything wrong".
GFG Alliance's main lender was Greensill Capital, which collapsed last month.
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Labour Health Minister Vaughan Gething said: "I think we need to be open about the fact that we should continue to look at the rules and standards that we have in Wales.
"We've got a good record in Wales. It comes from choices we make and we want the public to believe in the integrity of politicians and judge us on the honest differences that we really do have between us."
Asked whether Labour, if it is returned to power after May's Senedd election, would introduce an official lobbyists' register, Mr Gething responded: "I'm entirely open about it because I think what we'd need to do is try to have some consensus between parties to have effective rules that we all live by and all govern by."
In 2019, the Welsh government said it acted to restrict professional lobbyists' access to ministers after details of a meeting emerged.
Economy Minister Ken Skates met a broadband company in the assembly with a lobbyist present, despite repeated assurances from the government that ministers did not have formal meetings with commercial lobbyists.
A government spokesperson said a "misunderstanding" was to blame, and that it had "changed our processes" to stop it happening again.
Plaid Cymru's Delyth Jewell told Radio 4 she thought "there should be an official register for lobbyists in Wales and I think this is something the next Senedd has to return to certainly", but she said there was "no evidence that there's anything like" the levels of corruption in Wales compared with Westminster.
The leader of the Welsh Liberal Democrats, Jane Dodds, said: "We need to do things like, for example, making all ministerial meetings searchable online so we can actually make sure that something changes here."
Neil McEvoy, the leader of Propel, has long called for an official register of lobbyists in the Welsh Parliament.
His party is proposing that all corporate lobbyists must record details of their lobbying, its purpose, their clients and how much money was involved.