The boss of a multi-million pound company under fire for the alleged mistreatment of asylum seekers in Glasgow has said they would “’fess up” to mistakes as he confirmed one kitchen had been shared between 40 vulnerable people.

Serco chief executive Rupert Soames also said that there was “no evidence” his staff were abusing those in their care.

Keith Vaz, the head of the influential Commons Home Affairs Committee, is due to visit Glasgow on Friday to investigate the reports.

In a statement released on the eve of his trip, Serco admitted that allegations that a single kitchen was being shared between 40 people were “substantially correct”.

It said a shortage of accommodation in Glasgow had forced it to use a 90-person hostel with a "small" kitchen in recent months.

Serco said it was in the process of cutting the numbers staying at the address, because the "catering facilities were less than satisfactory".

The company also said that it had been unable to investigate reports staff had taunted asylum seekers with handcuffs and threats of deportation.

The firm said it had received no complaints and had no details of the circumstances behind the allegations.

It also said that it had no details of an alleged incident in which housing officers sprayed air freshener at asylum seekers, while laughing and holding their noses.

It added: “On balance, and without any evidence to the contrary, we believe this story to be untrue.”

The company said it had investigated allegations of blood splattered walls, which it said were found to be untrue as the substance was fruit juice.

Mr Soames, a grandson of Winston Churchill, said: “We care deeply about the welfare of the 4,600 often vulnerable people we are looking after in Scotland.

"We have investigated every allegation that has been made, and have found no evidence of mistreatment, and in some cases the stories were overblown or untrue.

"We have a fantastic team in Scotland providing an outstanding level of care, often in difficult circumstances, and there is no evidence that our people are treating asylum seekers badly.

"I am sure we do make mistakes from time to time, but where we do, we will ‘fess up to them and work hard to fix them.”

Serco houses 4,600 asylum seekers in Glasgow, in 1,860 properties.

The service is delivered through a subcontractor Orchard & Shipman, on behalf of the Home Office.

Last week David Cameron suggested MSPs should investigate.

But Mr Vaz has called on the Home Secretary Theresa May to get "a grip" on the situation.