As many as 1.25 million people - including more than 300,000 children - were "destitute" in the UK at some point in 2015, according to a new report.

The Joseph Rowntree Foundation report, commissioned in response to perceptions that extreme poverty in the country has risen in recent years, showed that 1,252,000 people - including 312,000 children - were destitute, defined as being when someone lacked two or more basic essentials such as shelter, food, heating, appropriate clothing or basic toiletries.

The study found that of those who were destitute, four-fifths were born in the UK and that almost a third had a "complex need" - long-term homelessness, substance misuse or mental health problems.Young single people, particularly men, were more likely to be destitute but there are also considerable numbers of families living in destitution.

The report shows that while there was no single cause, most people have been living in poverty for some time before "tipping into destitution" with the most common causes being the extra costs of ill health and disability, the high costs of housing and other essential bills, unemployment or a financial shock like a benefit sanction or delay.

Julia Unwin, chief executive of the foundation, said the number of people living in destitution in the UK was "shocking". "It is simply unacceptable to see such levels of severe poverty in our country in the 21st century. Governments of all stripes have failed to protect people at the bottom of the income scale from the effects of severe poverty, leaving many unable to feed, clothe or house themselves and their families."

Ms Unwin said root causes - such as the low incomes some families are living on and "financial shocks" such as benefits delays or family breakdowns - must be addressed.

"Government, businesses and communities need to work together to provide better emergency support, make essentials more affordable and create better jobs if we are to end destitution in the UK."