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* Barclays CFO Lucas, General Counsel Harding to retire
* Will only leave when replacements found, likely to be sometime
* Lucas under investigation for 2008 Qatar fundraising
* Lucas says appropriate time "to pass the mantle on"
By Steve Slater and Paul Sandle
LONDON, Feb 3 (Reuters) - Barclays said its financedirector Chris Lucas and its top legal expert are to retire,adding to change at the top of the British bank as it strugglesto put a series of scandals behind it.
Lucas, aged 52, has been finance director for a tough sixyears that spanned the global financial crisis, but the pastnine months have been particularly difficult.
He is one of four current and former employees beinginvestigated by UK authorities regarding a capital injection byQatar in 2008.
Group General Counsel Mark Harding will also retire, thebank said in a statement on Sunday.
Both will remain in their roles until their successors havebeen found and an appropriate handover completed.
The bank said headhunters had been appointed, but itexpected the process to take "a considerable time" to complete.
It could take up to a year to fill Lucas's position, peoplefamiliar with the matter told Reuters earlier on Sunday. SkyNews first reported Lucas would leave.
Sources said Lucas's departure was not linked to theinvestigations into Qatar. He is also the only one of Barclays'executive directors still in his post after the bank was fined$450 million in June for rigging the Libor global benchmarkinterest rate.
New Chief Executive Antony Jenkins is attempting to move onfrom the bank's troubles, which also include the mis-selling offinancial products, but that is proving a challenge.
The Financial Times reported on Friday that UK authoritiesare looking into allegations that Barclays lent Qatar Holdingmoney to invest as part of the rescue fundraising four yearsago.
British rules forbid a public company from giving financialassistance in order to acquire its shares.
Jenkins said Lucas and Harding both told him late last yearthey were considering stepping down. "Their decision to retirewas theirs alone," he said.
Lucas has had health problems and although that has notaffected his ability to do his job, it influenced his decisionto retire, one of the sources said.
"Now is the appropriate time ... to begin my retirement frommy role on the board and executive committee, and to pass themantle on to a successor," Lucas said in a statement.
Jenkins is due to unveil plans to streamline and reviveBarclays on Feb. 12 and he has also promised to improve cultureand standards across the bank's 140,000 workforce.
The CEO said on Friday he will not take a bonus for 2012,saying he should "bear an appropriate degree of accountability"for the difficult year the bank endured.
"The execution of our change programme will take place overthe next 5-10 years, and both Chris and Mark feel that now isthe right time for them, personally and professionally, to passthe baton on in their respective roles to executives who cancommit to seeing that programme to completion," Jenkins said.
Harding, 55, joined as general counsel in 2003, and hasresponsibility for legal issues throughout the bank, and as suchhandled Barclays' settlement with British and U.S. authoritieslast year for its manipulation of Libor rates.
Harding was previously general counsel of UBS's investment bank and a partner at law firm Clifford Chance.
Former Chief Executive Bob Diamond, Chairman Marcus Agiusand Chief Operating Officer Jerry del Missier all left last yearfollowing the Libor scandal.
Lucas, who joined the Barclays board in April 2007 fromPricewaterhouseCoopers, was paid almost 4 million pounds eachyear in 2011 and 2010, including long-term awards.
Jenkins and his chairman David Walker, are likely to begrilled on standards at the bank by British lawmakers when theyappear before the UK banking inquiry on Tuesday.
