Opposition politicians are calling on the government to come clean on its links to Enron.

The calls follow claims that the bankrupt firm's bosses were given access to government ministers after the company made donations to Labour coffers.

The Lib Dems, with Tory backing, are also demanding information about the government's links to Anderson - a firm that has carried out work on behalf of the government and has close links to the Enron scandal.

The prime minister's spokesman said it was "certainly not the case" that Enron was granted access to ministers as a result of any donation.