Chancellor George Osborne has said he would be "very happy" for the government to consider publishing the personal tax returns of ministers.
Interviewed in Saturday's Daily Telegraph Mr Osborne said: "Personally, I don't set my face against it."
He added: "They do it in America. My personal principle has been make the rules in general more transparent."
It comes after a public row between Boris Johnson and Ken Livingstone over their tax payments.
The pair, both candidates for Mayor of London at next month's election, were involved in angry exchanges last week amid accusations of avoiding income tax by channelling earnings through companies.
Mr Johnson and Mr Livingstone have now published their tax records, as have the Liberal Democrat candidate Brian Paddick, and the Green Party's Jenny Jones.
The other candidates are Carlos Cortiglia of the BNP, independent Siobhan Benita and Lawrence Webb, of Fresh Choice for London.
Mr Osborne told the Telegraph: "When it comes to publishing tax returns, personally, I don't set my face against it.
"But we have to think through the issues. You have to think through the advantages and disadvantages. We have got to think through the issue of taxpayer confidentiality, which is a very important principle in Britain."
Business Secretary Vince Cable echoed Mr Osborne's calls and told the Telegraph: "I'm quite happy to be open about it. I have no problem with my tax return being published while I am in government."
BBC correspondent Chris Mason quoted a Downing Street source as saying the government had no plans to bring this idea forward immediately, but adding: "We have been at the forefront of transparency so we are always happy to hear about ways of becoming more transparent."
A source close to the Deputy Prime Minister and Liberal Democrat leader Nick Clegg told our correspondent Mr Clegg has "no objection in principle" to the idea.
Earlier Nigel Farage, the leader of the UK Independence Party, told BBC Radio 4's Any Questions it was a bad idea.
"How far back do we go? Do we ask for medical records?" he asked.
Mr Farage said his fear was that it would put successful business people off a career in politics.