Bob Diamond has made clear he is staying on as Barclays CEO, writing in an email to staff it is his "responsibility to make sure" another scandal cannot happen again.
His statement comes hours after the bank's Chairman, Marcus Agius, stood down in the wake of the Libor scandal, where Barclays was fined £290m for manipulating the rate at which banks lend to each other.
Diamond wrote to staff at Barclays: "It is my responsibility to make sure that it cannot happen again. I love Barclays and am proud of all of you.
Under pressure: Defiant Diamond insists he is staying on
"Make no mistake the actions taken in this incident were against all of the principles we live by."
He continued: "A small minority let us down... We need to rebuild bonds of trust with the society we serve."
The bank said Agius will remain in post until an "orderly succession is assured" and added Barclays non-executive director Sir Michael Rake has been appointed deputy chairman.
Agius released a statement saying the buck stopped with him. "Last week's events - evidencing as they do unacceptable standards of behaviour within the bank - have dealt a devastating blow to Barclays reputation.
"As chairman, I am the ultimate guardian of the bank's reputation. Accordingly, the buck stops with me and I must acknowledge responsibility by standing aside."
Pressure remains on Barclays chief executive Bob Diamond, who is set to be grilled by the Treasury select committee on Wednesday.
There were growing questions about how much he knew about what was going on after it emerged that Barclays staff mistakenly thought they had been instructed by the Bank of England to lie in their Libor submissions.
On Monday morning Ed Miliband repeated his call for Diamond to step down as CEO of the bank in the wake of the scandal.
Deputy prime minister Nick Clegg has also heaped pressure on Diamond, saying the "buck stops at the top." "I'm like everybody else in this in that now that the chairman of Barclays has fallen on his sword and has taken responsibility for what has happened, everybody is asking when are the other senior people at the top of Barclays going to take responsibility for the things that happened on their watch," he said on Monday.
"I don't think it is for politicians to individually hire and fire bankers, but I do think the buck stops at the top."
Labour MP and member of the Treasury select committee John Mann released a statement on Monday asking further questions of the bank, including asking "When will Bob Diamond resign?"
Diamond's memo comes after the Serious Fraud Office said it hoped to decide within a month on whether a criminal prosecution in relation to the rate-fixing was appropriate.