The tiny European principality says several executives of the Monaco-based company UNAOIL had been questioned over the past few days and that their homes had been searched.

“These searches and interviews took place in the presence in the presence of British officials as part of a vast corruption scandal which implicates several foreign companies active in the oil sector,” the statement said.

“Evidence will be used by British officials as part of their investigations.”

Few further details were made available and Monaco’s government did not immediately return messages. A UNAOIL spokeswoman said the company “has no comment at this time”.

UNAOIL was at the centre of multi-part exposé published Wednesday by the Huffington Post and Australia’s Fairfax Media, which accuses the business of having “systematically corrupted the global oil industry” by delivering millions in bribes on behalf of well-known multinationals.

The publications said they drew on information gleaned from hundreds of thousands of internal emails between 2002 and 2012 for their six-month investigation.

Fairfax, which described the trove as “the biggest leak of confidential files in the history of the oil industry,” said the files carried evidence of bribes paid to Middle Eastern oil chiefs and other officials, sometimes with the knowledge – and occasionally with the active participation – of the multinationals involved.

AP