A Czech Interior Ministry commission has cleared the former mayor of Vienna, Herbert Zilk, of spying for the Czechoslovak communist secret police in the nineteen-sixties.

The commission said the allegations -- which Mr Zilk denied -- were unproven and unconfirmed.

The case led to the Czech President, Vaclav Havel, withdrawing a high state honour which Mr Zilk was due to receive earlier this year.

The Czech Foreign Ministry has presented a formal apology to Mr Zilk; the President's office has said that Mr Zilk has been invited to meet Mr Havel next week.