File picture: Toby Melville, Reuters

Shares in Barclays headed for their biggest one-day fall since 2009 on Thursday, extending losses after UK finance minister George Osborne said its CEO will face tough questions about the banks attempts to manipulate key interbank rates.

Shares in Barclays were down 14 percent at 170 pence by 14:03 SA time, having earlier fallen as low as 160.75.

Shares in other UK banks also fell, with Osborne saying that the FSA is continuing to investigate other institutions. RBS was down 11.5 percent and Lloyds was down 6.5 percent. - Reuters