Jeffrey Cook was convicted of misconduct in public office in January after a long-running criminal investigation into allegations bribes were paid to top officials in Saudi Arabia.

Cook, 67, had also been charged with overseeing corrupt payments to middlemen to obtain lucrative deals with the Saudi Arabian National Guard.

But he and John Mason, who prosecutors said was the accountant and part-owner of the business of the middlemen, were acquitted of corruption in January after a trial at Southwark Crown Court.

Cook and Mason had pleaded not guilty to paying bribes to top Saudi officials including Prince Miteb bin Abdullah, son of the late King Abdullah, between 2007 and 2012.

The case largely focused on GPT Special Project Management, a now-defunct subsidiary of Airbus. Its sole business was to provide communications systems to the Saudi Arabian National Guard under a contract with the MoD.

Prosecutors had alleged Cook and Mason were at the heart of "deep corruption" as part of which bribes of more than 9.7 million pounds ($12.1 million) were paid to Saudi officials and intermediaries between 2007 and 2010.

Cook and Mason, however, said the British government approved millions of pounds of payments because they were in the country's financial and strategic interests.

Tom Allen, representing Cook, said senior British officials, politicians and diplomats knew and consented to payments totalling nearly 60 million pounds from 1978 onwards.

Cook was found guilty of one count of misconduct in public office, relating to payments received when he worked for the MoD and before he joined GPT.

Judge Simon Picken sentenced him to 30 months in prison, saying his offending was so serious that only an immediate jail sentence would suffice.

(Reporting by Sam Tobin; editing by David Evans)

By Sam Tobin