Lord Ashdown said that 1,000 more British troops might have to be sent to Afghanistan to bolster coalition forces and combat the Taliban.
"I am not opposed to more troops going, I think they probably will be necessary," he said. "But I am not in favour of their going if we can't sort out what they are supposed to be doing when they get there."
His attitude to the war is at odds with other senior figures in the Liberal Democrats, including Vince Cable, the treasury spokesman, who favours planning for a rapid withdrawal of British forces from Afghanistan.
Liberal Democrat activists called for the Government to start pulling British troops out of the country and backed a motion tabled by grassroots members calling for "an end to the killing".
It urged the Government to "focus on concluding the Afghanistan mission and to report to Parliament in detail on progress towards a withdrawal".
Lord Avebury, the party's foreign affairs spokesman, will today accuse the Government of being "irresponsible" for failing to have a minister in place with responsibility for Afghanistan since the resignation of Lord Malloch-Brown.Reuse content