Why Gordon thinks he is on a promise
The word is, from usually impeccable sources, that President Barack Obama has decided to increase US forces in Afghanistan substantially.
There was a further White House meeting on the subject on Wednesday, but nothing has yet been announced officially in Washington.
Meanwhile Britain has said it will send 500 more troops, and in the run up to this announcement, Whitehall has received reassurances from the US president that the UK will not be left out on a limb.
According to some of those in the know, the US reinforcement could be as large as 45,000. This would amount to a dramatic endorsement of the counter-insurgency strategy proposed by General Stanley McChrystal and a reversal for Vice-President Joe Biden who questioned the value of sending more men and women.
Although Gen McChrystal has been widely reported as asking for 30-40,000 more troops, insiders say he actually looked at a variety of options that ranged from no boost (which would have involved giving up certain areas in order to concentrate existing numbers) to a thumping 60,000 more.
Announcing Britain's increase today the country's senior serving officer, Air Chief Marshal Sir Jock Stirrup hinted that although he did not want to pre-empt the US Joint Chiefs, "I'm pretty confident how it's going to come out".
President Obama is set to announce the result of his Afghan policy review soon. Some suggest that confirmation of a big reinforcement may be timed to coincide with a NATO defence ministerial meeting in Bratislava next week in the hope of influencing some other members to boost their contributions.
Gordon Brown, speaking in the House of Commons this afternoon, said that Britain's extra 500 would be committed under certain conditions: that Afghan forces in Helmand will increase substantially; that British troops can be properly equipped; and that other NATO allies also send more troops.
He revealed that although the Kabul government had honoured a promise to send more Afghan troops to Helmand after this summer's Panther's Claw offensive, they had actually dispatched disappointingly under strength units. The most serious doubts in Washington and London now centre on the Afghans' ability to deliver. They are waiting for a clear result to emerge from August's presidential poll and for President Karzai, assuming he is confirmed in power, to put in place an effective anti-corruption programme.