Barclays said on Sunday its Finance Director Chris Lucas and its General Counsel Mark Harding are to retire from the British bank, which is trying to emerge from a troubled nine months.

They will remain in their roles until their successors have been appointed and an appropriate handover completed. The search for replacements is underway, but the process will take "a considerable time to complete," Barclays said in a statement. Their decisions to retire was theirs alone, the bank said.

Lucas has been finance director for a tough six years that spanned the global financial crisis. He is one of four people being investigated by UK authorities regarding a capital injection by Qatar in 2008.

(Reporting by Steve Slater; Editing by Paul Sandle)