Mike Nesbitt '“ I will publish my tax returns today

In a short statement this morning issued via the UUP press office, Mr Nesbitt said: “I am happy to publish my tax return and will do so later today.”

The DUP leader Arlene Foster has also pledged to publish her tax returns in full.

Prime Minister David Cameron published a summary of his taxes after criticism about shares he held in an offshore fund set up by his father Ian, revealed in the Panama Papers leak.

Scottish Labour leader Kezia Dugdale and her Conservative counterpart Ruth Davidson made their tax returns public on Saturday.

Ms Dugdale said she was making the financial information public as a result of the Panama Papers scandal and called on the other party leaders to do the same.

Nicola Sturgeon published her tax return yesterday, as did Scottish Liberal Democrat leader Willie Rennie, and she pledged to do the same each year she remains First Minister.

Ms Sturgeon’s return for 2014-15 revealed she had a total income of £104,817 and was charged £32,517 in income tax.

An SNP spokesman said: “The First Minister’s only income is the salary she receives as an MSP and First Minister.

“Nicola Sturgeon pays tax on her full salary entitlement but only draws her salary at its 2008/09 level – the balance is automatically paid to the Scottish Government for use in general public spending.

“As a result, in 2014/15 the First Minister paid around £3,000 into the Scottish Government consolidated fund.”

Mr Rennie’s papers for the same year show his income was £52,283 and he was charged £10,480.20 in income tax.