British security firm G4S on Friday said both its chief operating officer and global events director would resign after an internal review into its Olympic staffing contract failure.

However, Chief Executive Nick Buckles kept his job despite the high profile debacle which has threatened to jeopardise future core work with Britain's government.

"Whilst the CEO has ultimate responsibility for the company's performance, the review did not identify significant shortcomings in his performance or serious failings attributable to him in connection with the Olympic contract," G4S said in a statement on Friday.

(Reporting by Rosalba O'Brien and Neil Maidment)