Ed Miliband vows not to 'gloat' over victory
Labour leader Ed Miliband says he will not join in the "gloating" over his party's victory in the Oldham East and Saddleworth by-election.
At a speech to the Fabian Society on Saturday, Mr Miliband will say Labour must become again "the standard-bearer of the progressive majority."
And in an article for the Guardian, Mr Miliband also says that he will co-operate with "courageous" Lib Dems.
The by-election saw Labour boosting its majority from 103 to over 3,500.
After the result Mr Miliband said the result showed the Lib Dems had made a "tragic mistake" in joining the Conservatives in coalition.
In his speech Mr Miliband will say: "We must rebuild ourselves as a broad movement of the British mainstream that politicians have talked about for decades but often not understood."
As the government's spending cuts begin to impact as it aims to save £81bn in four years, Mr Miliband will set out how he sees Labour's position: "I want to become the voice and hope of those who feel squeezed by an economic system that promised to liberate them.
"I want us to articulate the frustration of people who are fed up with bankers taking vast public subsidies and then rewarding themselves for failure while the rest of the country struggles.
"I want us to be the party that answers the call for a fairer sharing of the nation's wealth, strong and responsive public services and a different kind of politics."
Mr Miliband will say that he hopes the Liberal Democrats will realise their "mistake" in joining the Conservatives in coalition.
"Forgive me if I decline to join those of you who are gloating at the expense of the Liberal Democrats.
"Their decision to join a Conservative-led government was a tragic mistake, and I hope they come to see that in time."
In his Guardian article Mr Miliband says he "respects the choice" of Lib Dems who have decided to stay and fight for the soul of their party.
'Courageous' Lib Dems
"We want to co-operate with them in parliament and outside to fight against the direction in which this Conservative-led government is taking our country.
"We will work with those who have the courage of their convitions."
In Thursday's by-election, Debbie Abrahams finished 3,558 votes ahead of the Lib Dems with 14,718 votes. The party's share of the vote increased from 31.9% to 42%.
But Lib Dem Elwyn Watkins fractionally increased the party's vote share on the 2010 result from 31.6% at the general election to 31.9%.
The Greater Manchester by-election was called after a special court found ex-Labour minister Phil Woolas made false statements about Mr Watkins in May's general election, in which Labour retained the seat by just 103 votes over the Lib Dems.
The ruling invalidated the result and resulted in Mr Woolas being barred from politics for three years.