Former Labour leader Ed Miliband has called for an end to the "secrecy and abuses" of tax havens.
Speaking on ITV's The Agenda with Tom Bradby, Mr Miliband called for sweeping changes to the UK's tax policy, including ending non-domiciled status, which allows some British citizens resident abroad to limit the tax they pay on foreign earnings.
"We go on about Panama - the top country in the world for tax avoidance is the UK," he said.
Mr Miliband also stood up for David Cameron, who has faced intense criticism over benefiting from his father's investment fund.
"I understand the prime minister defending his father and I understand it was upsetting for him," he said.
Dennis Skinner was booted out after refusing to withdraw the comment he made to the Prime Minister in a debate over the tax row.
The Labour leader declared £1,850 in additional income, but was fined £100 for submitting his tax return a week late.
Chancellor George Osborne has released his tax return after the prime minister urged him to publish the records.