An assessment centre in Norfolk that decides whether disabled people are fit for work has been criticised for not being accessible to wheelchair users.
Atos, the company which runs the government assessments, has a second floor office in St Marys House, Duke Street, Norwich.
North Norfolk MP Norman Lamb said it was "fundamental" the service was accessible for all disabled people.
The government said the possible use of ground floor space was being looked at.
A Department for Work and Pensions (DWP) spokesperson said: "DWP is currently investigating options for the ground floor at the Norwich site."
An Atos spokesperson said home visits could be arranged where necessary.
Liberal Democrat Mr Lamb said he was amazed a centre that decided whether disabled people were fit enough to work could not see people in wheelchairs.
"It was a constituent who said to me the assessment centre for disabled people was on the second floor of a building in Norwich and it did strike me as extraordinary," he said.
"It seems to me as a priority they should be looking to locate this somewhere that is accessible for all disabled people.
"It does not make sense for a centre for disabled people to be based on a second floor - it leaves one somewhat amazed, but that's what happened.
"We need to try and make sure an alternative is found as soon as possible."
The building has a lift, but this cannot be used in the case of a fire which means people in wheelchairs are not able to be assessed at the Duke Street premises.
In a statement, Atos Healthcare said: "The government have provided St Mary's House to us to carry out assessments on their behalf.
"We let people know about access prior to their visit and will reschedule an appointment at the nearest ground floor assessment centre or arrange a home visit where necessary."
The nearest alternative assessment office is in King's Lynn, about 45 miles from Norwich.