The Joseph Rowntree Foundation (JRF) says a "turning point" has been reached in the fight against poverty following the first sustained increases in child and pensioner poverty for 20 years.
Its state of the nation report said poverty rates increased last year, leaving 14 million people living in poverty, including four million children and 1.9 million pensioners.
Campbell Robb, chief executive of the JRF, said: "These worrying figures suggest that we are at a turning point in our fight against poverty.
"Political choices, wage stagnation and economic uncertainty mean that hundreds of thousands more people are now struggling to make ends meet. This is a very real warning sign that our hard-fought progress is in peril"
Responding to the report, the Bishop of Durham Rt Revd Paul Butler (pictured above), on behalf of the Church, said: "I am deeply concerned by the Joseph Rowntree Foundation's latest findings, showing a rise in poverty over the past five years, and the negative impact this has on people's health and relationships.
"The very high rates of poverty among single parent families (46%) and larger families (39%) are especially worrying, knowing that worse is to come with the continuing freeze in benefits and the introduction of the two-child limit.
"It was encouraging to hear of the Government's amendments to Universal Credit in the recent Budget, which are a step in the right direction. But it is now clear that much more will need to be done to achieve the policy's aims to make work pay and reduce poverty."
A Government spokesman said: "We are spending an extra £4.2 billion on pensioners, carers and disabled people next year, and continue to spend around £90 billion a year supporting people of working age, including those who are out of work or on a low income.
"Since 2010, the number of people in absolute poverty has fallen by over half a million, pensioner poverty remains close to historically low levels and we are supporting parents with the cost of bringing up children by doubling free childcare.
"We have given the lowest earners a significant pay rise through the National Living Wage, and are introducing Universal Credit to make sure it pays to be in work."