Barclays' finance director Chris Lucas is retiring, over six months ahead of schedule, due to unspecified health reasons.
Lucas, who announced his retirement amid the Serious Fraud Office's (SFO) ongoing investigation in the bank's dealings with Qatar during the credit crisis, was set to step down on 28 February 2014.
"My health was a key factor behind my decision to step down which we announced in February," said Lucas, aged 52.
"Whilst I had hoped to be able to continue working until early next year it is now clear to me that with my health as it is this will no longer be possible.
"I want to do the right thing by Barclays, my family, and myself, and therefore I have reached the difficult decision to step down sooner. I feel confident that I leave Barclays financially robust and well placed to continue to serve its customers, clients, shareholders and other stakeholders."
JPMorgan executive Tushar Morzaria will now take up Lucas' role on 15 October while Peter Estlin, Barclays' group financial controller, will serve as acting finance director until Mozaria's arrival.
Retirement and SFO Probe
After the onset of the credit crisis, Barclays raised £4.5bn (€5.2bn, $6.9bn) in new shares in June 2008 and then a further £7bn in November that year from Qatar.
Lucas was one of four current and former senior executives the bank said in a 27 July investor update were subject to an Financial Conduct Authority investigation into the "sufficiency of disclosure in relation to fee payable under certain commercial agreements and whether these may have been related to Barclays Capital raisings in June and November of 2008."
On 20 August last year, the SFO said it had opened an investigation"into certain commercial arrangements between Barclays Bank and Qatar Holdings in 2008".
The probe is focusing on whether Barclays lent the Qatar's sovereign wealth fund money to buy its own shares during the height of the financial crisis.
The UK Treasury will grant the Serious Fraud Office £2m to help it investigate Barclays' fundraising activities during the onset of the financial crisis after it avoided a state bailout and instead received cash from Qatar authorities.
At the end of July this year, the UK government pledged an extra £2m to help the SFO conduct its criminal probe after Qatar Holding, a part of the Qatar Investment Authority, gave the bank a chunk of cash to save it from a publically funded bailout.
Lucas announced departure came one week after his name was also mentioned in a court battle between Barclays and Guardian Care Homes, a British healthcare company that is suing the bank over a disputed interest rate contract.