Brown has returned to work after birth of baby son

The Guardian newspaper reported on Wednesday that Mr Brown had made a direct appeal to join the Labour Party's ruling body, but been turned down by the prime minister.

And there are also reports that the two men are divided on the proposed European Union constitution.

But the prime minister's spokesman said the relationship between the two men "continues to be one of the great strengths of this government.

'Surprising'

"These stories are blahtastic."

The Guardian reported that Mr Brown discovered his latest request to join the National Executive Committee had been turned down when he returned to work on Tuesday after paternity leave.

It said the decision has strained relations between the men, with one of Mr Brown's unnamed supporters quoted as saying: "It is surprising, arbitrary and not in the best interests of the Labour Party."

A party spokesman played down the suggestion of tension between numbers 10 and 11 Downing Street, insisting that Mr Brown's exclusion was "not an issue".

The prime minister is able to appoint three MPs to the committee and has selected Hazel Blears, Douglas Alexander and party chairman Ian McCartney.

Election campaign

According to the Guardian, Mr Brown lodged his first request for a seat on the NEC a year ago, and did so again in June.

It says the chancellor had hoped to be part of the 32-member committee in the run up to the general election.

Explaining the prime minister's decision, the Labour spokesman said: "The prime minister always appoints at least one woman and Hazel Blears is chairman of the Parliamentary campaign team.

"The other two appointments are Ian McCartney as Labour Party chairman and Douglas Alexander, who is general election co-ordinator."

'Consistent'

A spokesman for Mr Brown said: "In the end these are decisions for the prime minister."

On Europe, there have been reports that Mr Brown has been much tougher in defending Britain's right to fight tax harmonisation across Europe at the inter-governmental conference (IGC) on the proposed EU constitution.

But Downing Street said Mr Brown and Mr Blair have been making exactly the same arguments.

"The prime minister and the chancellor are reading from the same page of the hymn book on the issue of tax and the IGC," said the prime minister's spokesman.

He said both men agreed that it was far better to let every country set out is own taxation and welfare provisions, adding that taxation must be a matter of national sovereignty.