The Government has been urged not to criminalise squatting after a report found it would lead to an increase in some of the most vulnerable homeless people sleeping rough.
The report, published by Sheffield Hallam University on behalf of homeless charity Crisis, comes as the Government consults on plans to bring in laws making squatting a criminal offence and ending so-called "squatters' rights".
It said the new laws would result in the criminalisation of homeless people, who squat because accessing adequate affordable housing in England and Wales is so difficult, but would have little impact on levels of squatting.
The report, entitled Squatting: A Homelessness Issue, found most homeless squatters squat only as a last resort, after approaching and being turned away from, hostels, shelters and local authorities.
It added that homeless people who squat occupy empty, usually disused or abandoned property and there was no evidence of squatters displacing anyone from their homes.
The Government's proposals would see a new criminal offence of squatting brought in, along with steps to prosecute squatters for other offences they commit, such as criminal damage, burglary, or using electricity without permission.
The report said: "Strengthening laws or enforcement activity against squatters in occupied buildings is likely to have minimal impact on levels of squatting but significant impact on squatters themselves.
"Squatting, then, is a homelessness and welfare issue, not a criminal justice issue."
It added: "Criminalising squatting will criminalise a vulnerable homelessness population and is likely to increase the number of rough sleepers."
The report also found that squatters are more likely to have "significant welfare needs", including mental and physical health issues, compared to homeless people who have not squatted.
It said a recent study found that 34% of homeless squatters had been in care, 42% had physical ill health or a disability and 41% reported mental ill health.
Of homeless people who had not squatted, 19% had been in care, 27% had physical ill health or disability and 32% had mental ill health.
The report recommended that the Government should protect homelessness services from cuts and not introduce further criminal squatting offences.
It also said support and outreach services targeted at squatters should be provided and local authorities should ensure that homeless people are provided with effective advice and assistance to help them resolve their housing problems.
The report's author also suggested that more should be done to raise awareness about squatting as a homelessness issue and dispel myths about squatting being a "lifestyle choice".
Leslie Morphy, chief executive of Crisis, said: "It is clear from this research that many people who resort to squatting do so out of sheer desperation, and in appalling conditions.
"If the Government must change a law it should be to ensure all homeless people get the help they desperately need from local councils instead of criminalising some very vulnerable people."