One day short of his fifth anniversary as Liberal Democrat leader, Nick Clegg will today begin the process of "decoupling" his party from the Conservative Party with which it shares power in Government.
We are now closer to the next General Election than the last one and the Deputy Prime Minister will set out the differences between his party and David Cameron's.
The process known as "decoupling" will have to happen before the election in May 2015 - but with polls putting the Liberal Democrats in fourth place behind UKIP, Mr Clegg is keen to point out the different priorities in the Coalition.
He will insist the Liberal Democrats are firmly rooted in the centre ground whilst setting out the reasons why welfare reform has been "imperative".
And he will claim MPs on the right-wing of the Tory Party would have pulled a majority Conservative government in the direction of draconian welfare cuts.
Nick Clegg argues the Tories wanted £10 billion of welfare cuts in this months Autumn Statement but the Lib Dems agreed £3.8 billion.
They wanted a freeze on benefit payments, he will say, but we agreed 1%.
They wanted to penalise families with more than two children but we "rejected the more extreme reforms that had been put on the table."
Mr Clegg will add: "Both the Conservatives and Labour try to occupy the centre ground. Both get pushed off it by their tribal politics. But the Liberal Democrats are not for shifting."
The Deputy Prime Minister will also highlight differences between the Lib Dems and Conservatives over Europe and gay marriage.
He will say: "The Tory right dreams of a fantasy world where we can walk away from the EU, but magically keep our economy strong…where we can pretend the world has not moved on, and stand opposed to equal marriage."
In the months after the 2010 election, Nick Clegg firmly believed the Lib Dems should "own the coalition" and not constantly snipe from the sidelines.
But with two national opinion polls at the weekend, which put the Liberal Democrats on 9% and UKIP on 14%, Mr Clegg knows he must better define his party in the eyes of voters and he will do it, he says, by positioning his party in the centre ground.
He will claim his party is "better at negotiating" with the Conservatives and will warn those Lib Dem activists who are losing faith that the alternative is a "retreat to the comfort and relative irrelevance of opposition."
"We're not centre ground tourists," he will claim, "The centre ground is our home."