Tony Blair last night hosted an impromptu summit of European leaders in Downing Street.

Europe's "big five" met as speculation grows that a major land offensive against Afghanistan's ruling Taliban is imminent. Reports that the northern alliance is hoping to capture the city of Mazar-i-Sharif by the end of the week would clear the way for US troops to move in from neighbouring Uzbekistan.

A Downing Street spokesman described the meeting as "very useful" and claimed there was "absolute solidarity" over the war strategy.

The prime minister was originally due to meet with Germany's chancellor Schroeder and France's president Chirac and prime minister Jospin. Following a row over a British, French and German summit in Ghent last month, the leaders of Holland, Spain and Italy re-arranged their diaries over the weekend in order to participate. Belgian prime minister, Guy Verhofstadt and foreign policy chief Javier Solana represented the EU.