Nick Clegg has been clear throughout that he would participate in any debate to which he was invited.

So… why did the Lib Dems not take part in the debate?
Lib Dems deeply regret that he has been excluded from this debate. The blame lies squarely with David Cameron. Not only was he too scared to face the electorate in this debate, he was too scared to accept the consequences of being the only leader not taking part. That is a pretty contemptible double act of cowardice.

We wanted to ensure that at least one all party debate took place so we very reluctantly agreed to the current proposal. But it is outrageous that David Cameron’s cowardice has led to our exclusion.

BACKGROUND
The Tories would only agree be in one debate and they only agreed to take part in the first debate on condition they were not the only ones not taking part in the second debate – the broadcasters therefore excluded us in order to get an agreement. Liberal Democrats reluctantly accepted – the alternative was no debates at all.

VERDICT
“The one thing that is certain is that no one party is going to win the election outright.
That means that someone else will hold the balance of power on the 8th May.
Only a vote for the Liberal Democrats will keep Britain on track.”