The invasion was launched in November 2001 The House of Commons is to vote for the first time on whether UK troops should remain in Afghanistan – almost nine years after the war started.
There have been several statements and debates since the invasion in November 2001, but never a motion put to MPs.
The vote, on the question that “this House supports the continued deployment of UK armed forces in Afghanistan”, is expected at about 1800 BST.
More than 330 UK troops have died and around 10,000 are serving in the war.
The decision to join the US-led invasion was taken without a parliamentary vote, unlike the invasion of Iraq in 2001.
It was backed by the leaderships of all three main parties.
In June, Prime Minister David Cameron said he wanted UK troops out of Afghanistan within five years, but added he preferred not to “deal in too strict timetables”.
The Commons motion on troops in Afghanistan was tabled by the newly established Backbench Business Committee, which lays down the agenda for debate time not taken up by the government.
Green Party leader and Brighton Pavilion MP Caroline Lucas has laid down an amendment arguing the Commons “does not believe that there is a military solution to the crisis in Afghanistan; and supports the pursuit of talks to secure a regional solution, including a potential power-sharing agreement and ceasefire, thus enabling the swift withdrawal of troops”.
This is backed by Labour’s Paul Flynn, Katy Clark and Jeremy Corbyn, and Jonathan Edwards of Plaid Cymru.
There have been numerous ministerial statements and general debates about the war in recent years, without going to a vote.
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