In his speech during before the parliamentary vote on the war on 18 March 2003, he outlined why he did not believe there was a case for war, and that he believed there was no public support for such a decision:
There is huge public anxiety in Britain. That is the mark of a fundamentally decent society. All of us, whatever our views, whatever our parties, know that the kind of people contacting us are very different from many of those with whom we deal regularly. They are the kind of people who say, 'I have never contacted a Member of Parliament before,' or 'I’ve never been politically active before.' They are the kind of people who have never gone on a march or attended a vigil before. Another significant point is that, whether or not they agree with the Prime Minister, only a tiny fraction ever call into question his sincerity in this matter.
I have never done so and I do not do so today. But much as they detest Saddam’s brutality, they are not persuaded that the case for war has been adequately made at this point, they are worried about the new doctrine of regime change, they are wary of the Bush Administration’s motives, and they do not like to see Britain separated from its natural international allies.
The cross-party amendment is the correct amendment. It is tabled at the correct time, and, if passed, would send the correct signal. It is on those grounds that the Liberal Democrats will vote for it tonight.
He was heavily criticised for this stance at the time, and parliament was also hostile.
He was repeatedly asked to give way during this speech, after which the Speaker made clear that he would not, and faced heckling from senior ministers for his position.
He also faced opposition in the form of the media, which many people have remembered today:
This joke also barely works - snakes are vertebrates.