David Cameron has announced a £200m boost for his Big Society drive - as Labour's leader says his cuts are making society "smaller and weaker".
The PM said a Big Society bank would invest £200m from the financial institutions in the voluntary sector.
Ed Miliband said billions of pounds were being cut from voluntary groups across the country.
And Labour accused the PM of not being "straight with people" over cuts to Sure Start children's centres.
The row over the Big Society follows criticism from the retiring head of one charity that cuts were "destroying" Britain's "volunteer army".
Dame Elisabeth Hoodless told The Times on Monday that "massive" cuts to council spending would make it harder for people to do more in their communities.
At Prime Minister's Questions, Mr Miliband asked why Mr Cameron "doesn't listen to people who know about volunteering" and said charities up and down the country were concerned about the impact of spending cuts.
The Labour leader said Mr Cameron had promised to protect Sure Start children's centres but had cut funding by 9% and said there were predictions from childcare charity The Daycare Trust that 250 would close within a year.
He said even the Conservative leader of the Local Government Association believed Communities and Local Government Secretary Eric Pickles was "detached from reality" about the impact of the cuts.
And he asked Mr Cameron: "How do you expect people to volunteer at the local library if it is being shut down?"
But the prime minister accused Mr Miliband of "sniping" and said all parties supported the aims of the Big Society - in terms of devolving power to councils and communities.
He said he disagreed with Dame Elisabeth as the government was putting in £470m over four years into charities and voluntary bodies and a further £100m would be made available to help charities worst affected by spending cuts.
Mr Cameron added: "And something I can tell you for the first time today because of our deal with the banks, the Big Society bank will be taking £200m from Britain's banks to put in to the voluntary sector."
On Sure Start, he said the budget was "going up" from £2,212m to £2,297m and said the chief executive of the Daycare Trust, Anand Shukla, had said the government had "allocated sufficient funding for the existing network of Sure Start children's centres to be maintained".
But Mr Miliband said the government was "cutting billions of pounds from voluntary sector organisations up and down this country".
He said Mr Cameron was "cutting too far and too fast and society is becoming smaller and weaker, not bigger and stronger".
The prime minister said the Labour leader did not have "a single idea for making this country a better place" and should support the Big Society.
As noise levels rose in the Commons, Mr Miliband, who was a cabinet minister under Gordon Brown, joked: "You shouldn't get so angry, it will cloud your judgement - you're not the first prime minister I have said that to."
A spokeswoman for the Daycare Trust told the BBC that the government had removed the ring-fence around Sure Start budgets and the charity stands by its warning that 250 Sure Start Centres face closure.
The figures referred to by Mr Cameron related to the Early Intervention Grant to local authorities, which includes other projects as well as Sure Start, and cover 2011-12 and 2012-13. But they are lower than the budget for 2010-11, £2,483m.
Shadow Education Secretary Andy Burnham said: "David Cameron needs to be straight with people. The truth is that he's cutting Sure Start funding, not increasing it - that's what his own figures show.
"On top of a real terms cut for Sure Start, he's cutting funding for children, young people and families by 10.9% next year. No wonder the Daycare Trust is standing by its claim."
The government says it protected Sure Start's budget in cash terms in the spending review - although the ringfencing of the money was removed.