The ongoing tensions between Tony Blair and Gordon Brown have intensified.

Yesterday it was announced the prime minister will hold his monthly press conference at 10.00am today at precisely the same time that the chancellor will make a long planned speech on Britain's plans for leading tackling global poverty.

"Downing Street has long known Gordon was going to make an important speech at that moment," an ally of the chancellor told the FT. "But they still went ahead and staged the press conference at the same time."

Downing Street rejected these suggestions. "The timing of the press conference has more to do with logistics than politics," said one aide.

"The first week back after Christmas is always a congested time. Tony's instinct is still very firmly to work with Gordon and engage with him rather than isolate him."

The dispute surfaced after claims the chancellor was being excluded from general election planning.

The government has also been forced on the defensive by criticism that its response to the tsunami disaster has been mishandled.

Conservative co-chairman Liam Fox said: "When the people of the country are pulling together in the face of a tragedy, Blair and Brown continue their obsession with each other."

Simon Hughes, the Liberal Democrat president, added: "The prime minister and his senior ministers, including the chancellor, may have been embarrassed by their slow and limited early response.

"But internal rows and personal rivalries have no place in the days and weeks ahead."