The National Pensioners Convention (NPC) staged a rally of Parliament to lobby MPs for changes to pensions sooner than the 2012 date that has been indicated by the Government as part of its White Paper on pension reform.
The organisation, which represents more than 1,000 pensioner groups across the country, claims that up to three million pensioners will die before the link between pensions and earnings, abolished by the Conservatives in the 1980s, is restored.
NPC members want the Government to increase basic state pensions to £114 a week from the current figure of £84.25 to help tackle pensioner poverty.
Joe Harris, general secretary of the NPC, said: "The Government's White Paper on pensions contains nothing of immediate benefit to today's pensioners.
"Already one in five older people live below the poverty line and millions more are being forced into hardship by rising fuel and council tax bills.
"Yet the Government has been breathtakingly complacent on the issue, by refusing to substantially increase the basic state pension and delaying the restoration of the link between pensions and earnings until at least 2012.
"The question therefore is not whether the county can afford to provide a decent state pension for everyone, but whether MPs have the political will to do the decent thing."
A spokesman for the Department for Work and Pensions said: "Tackling pensioner poverty has been our first priority. Since 1997, initiatives such as Pension Credit have helped to lift more than two million pensioners out of absolute poverty and a million people out of relative poverty.
"On average pensioner households are £1,400 a year - £26 a week - better off in 2006/07, because of tax and benefit changes, than under the 1997 system. A pensioner is now less likely to be on a low income than people of working age."
Speakers at today's rally include MPs Kate Hoey and Kelvin Hopkins, who are among 96 MPs to have signed an Early Day Motion in support of the NPC's demands.
There are currently about 11 million pensioners living in Britain.