A catering giant caught up in the horsemeat scandal has supplied burgers to the Scottish Parliament.

Sodexo, which provides services at over 2,000 outlets including schools, care homes and the armed forces, withdrew beef from its UK sites after a frozen product tested positive for horse DNA.

It said yesterday that the situation was "totally unacceptable" and the products were being recalled "with immediate effect".

A Scottish Parliament spokeswoman said that, while written assurance had been received from Sodexo that supplies to Holyrood are not affected, its beef burgers have been taken off the menu there.

"Sodexo supplies only one frozen meat product to the Parliament, a beef burger, and purely as a precautionary measure, we have withdrawn it," she said.

"Sodexo have said: 'The service at the Scottish Parliament is not affected regarding the equine DNA issue'."

In a statement, the firm said: "Sodexo has had a proactive programme in place to ensure that there is no horsemeat in its supply chain.

"We demanded written assurances from across our supply chain that the products we purchase did not contain horsemeat, and additionally implemented an internal sampling programme.

"Despite repeated guarantees from our suppliers, our sampling has identified a frozen beef product which tested positive for equine DNA. This situation is totally unacceptable.

"We felt the only appropriate response was to withdraw not only this product but all frozen beef products. We will only re-admit into our catering operations products that have affirmatively passed DNA testing, pursuant to laboratory test criteria."

The company has launched an investigation into how beef products were contaminated with horse.