LONDON, Dec 21 (Reuters) - British engineering company Rolls-Royce RR.L denied a report in The Guardian newspaper on Wednesday that it had in the past sold equipment to Iran by exploiting a series of loopholes in U.S. sanctions.

"Rolls-Royce refutes any accusation that it has traded 'in secret' in Iran or that it circumvented U.S. sanctions," said a Rolls-Royce spokesman in an emailed statement.

"We conduct business in all countries, including Iran, in accordance with all relevant UK, EU or other national sanctions and export control regulations. This includes applying for export licences, when they are required, and complying strictly with their terms and conditions."

The Guardian cited a company memo from 2009 and its report said that Rolls had been selling equipment to Iran for decades despite the political risk of being seen to avoid U.S. sanctions.

(Reporting by Sarah Young; Editing by Keith Weir) ((; +44 20 7542 1109; Reuters Messaging: