Hamid Karzai

Tony Blair has promised to work in partnership with the interim Afghan leader Hamid Karzai to tackle the challenges facing Afghanistan.

But the prime minister refused to be drawn over the further commitment of British troops in Afghanistan despite an appeal from the stricken country's interim leader.

In a Downing Street press conference following a meeting between the two leaders on Thursday, Blair looked ahead to a more prosperous future for Afghanistan but warned that "there are still huge challenges that lie ahead".

The prime minister said he was "very proud of the role our troops have played" but declined to give any commitment to participating in the larger peacekeeping force which Karzai favours. Other countries would make a contribution, he said, but added that there would be a "range of discussions" about the size of the force.

"Our commitment to the Afghan people has not ended. We still have unfinished business," the prime minister told journalists. Some Taliban members continue to pose a threat and there was still the need to bring Osama bin Laden to justice.

Hamid Karzai told reporters that while reports of requests for 30,000 troops may not be accurate, Afghan chiefs in areas outside Kabul, where the International Security Assistance Force is currently deployed, had requested the presence of peacekeepers.

He paid tribute to the victims of the US terrorist attacks and attacked the previous Taliban regime.

"A horrible, horrible face. A face which knew nothing but torture, killing and destroying lives. They did that in Afghanistan and they also did that in the most genuinely shocking and unbelievable way in New York. Our people really know the pain of the families of the people who died," he said.

Karzai said his people had demanded a "measure of commitment from the international community" regarding the number of troops sent to his country. More troops would be a symbol of commitment but the exact number would be a matter for military experts.

"All of the people I have received...have asked for the continuation of the force in Afghanistan and the expansion of that force to other parts of Afghanistan," he said.

In an earlier briefing to journalists, Tony Blair's official spokesman had been keen to focus on what had been achieved so far.

"The establishment of the interim government was way beyond the dreams of many of us a few months ago," he said.

Number 10 pledged that the West was "in this for the long term" to bring about the stability that would allow people in Afghanistan to live normal lives.

Downing Street stopped short of agreeing to the Afghan request for the number of foreign troops to be increased.

"We always said the ultimate goal is that the Afghans should police themselves and should have their own army. There are short-term, medium-term and long-term objectives to achieve this. We are facing a unique situation. It is not surprising that as the situation evolves people will have to think through where we are and the response to that," said the spokesman.

Except for this issue Number 10 was keen to talk up relations between the two leaders.

The prime minister said their meeting, which saw Karzai sit in on the final 10 minutes of the Cabinet's weekly gathering, was evidence of Britain's "complete and continuing commitment to Afghanistan".

At the Cabinet meeting Karzai spent 10 minutes with ministers who stood on his arrival and met his speech with loud applause.

He had talked about the need to rebuild Afghanistan - and that he now had the money to do so thanks to the commitments made at the Tokyo conference.

The chairman's priorities had a familiar ring about them to ministers - education, health and transport.

The spokesman went as far as to highlight that "he spoke in a very impressive way without notes".

Looking ahead to the reconstruction of the war-torn country, Blair said: "There is huge potential in Afghanistan."

Conceding that this would be a "massive" task, Blair said the two countries would be "genuine partners in a more stable region and world".

Chairman Karzai is visiting the UK on his way back to Afghanistan from a visit to America, where he met president George Bush. He also attended the president's State of the Union address to Congress as guest of honour.

The UK has committed £200 million over the next five years for reconstruction and humanitarian assistance. The pledge is in addition to the sums contributed by the Department for International Development to the World Bank, European Union and Asian Development Bank who will also be providing funds to Afghanistan in future years.

Also announced was a scheme aimed at attracting back Afghan professionals, such as doctors and teachers who had fled to the UK during the period of Taliban rule.

The two countries had agreed to a scheme aimed at ending the "brain drain" from Afghanistan. British companies involved in reconstruction projects would guarantee employment to Afghans who went back.