A row today erupted over fast-food chain McDonald's sponsorship of a high-profile event at the Labour party conference in Brighton.

Labour chiefs have been forced to deny reports the burger chain is sponsoring the £15,000 event on condition the Prime Minister, Tony Blair, attends.

It has been reported the party has been "auctioning" off commercial opportunities in order to raise more than £4 million during the week of the conference, which begins on September 30.

The claims immediately provoked criticism that Labour is guilty of cosying up to big business.

GMB union leader John Edmonds said: "I hope this is not a first step towards renaming us the McLabour party.

"If a company is prepared to pay £15,000 for the privilege of a glass of warm white wine with the Prime Minister then it can afford to pay decent wages."

But a party spokesman said it was not true McDonalds had agreed to sponsor the reception on the grounds Mr Blair would attend.

He confirmed the US corporation had agreed to sponsor the food and drink for 450 guests at the event.

The spokesman added: "McDonald's have sponsored events in the past. Last year they sponsored the exhibitors' reception and this year they plan to sponsor another reception.

"But there is absolutely no agreement whatsoever about the involvement of the Prime Minister at any reception that they would sponsor."

The reception, to be hosted by party chairman Charles Clarke, will take place on October 1, the eve of Mr Blair's keynote speech to conference delegates.

A McDonald's spokesman said the company had sponsored a reception at the Labour party conference, the Conservative Party conference and the Liberal Democrat party conference for the past two years.