Pressure on Ms Jowell increased at the weekend when the Sunday Times newspaper reported she had signed a document in 2000 allowing her husband to get a loan secured on their London home.
The newspaper said the loan was repaid with $600,000 which prosecutors allege Italian Prime Ministers Silvio Berlusconi placed in an offshore hedge fund to reward Mr Mills for testifying in favour of him at a corruption trial.
The case has threatened to link one of Prime Minister Tony Blair’s most loyal government ministers to a corruption allegation against Mr Berlusconi.
Prosecutors in Italy are investigating whether the money came from Berlusconi, and whether that amounted to a crime.
Mills, a tax lawyer, testified in 1997-98 corruption trials against Berlusconi.—Reuters