Gordon Brown on his anger over Sir Fred Goodwin's pension
Gordon Brown has repeated his threat of legal action against ex-Royal Bank of Scotland chief Sir Fred Goodwin over his "unacceptable" £16m pension.
The PM said he shared public "anger" about the size of the pension and was "considering every legal means at our disposal" to get some of it back.
Sir Fred has rejected pleas to return it, claiming ministers approved it.
The Tories say Mr Brown's anger is "synthetic" as ministers knew about the pension and should have stopped it.
Sir Fred's pension pot doubled to £16m last October, guaranteeing the 50-year-old £693,000 for life, when he agreed to take early retirement. It is thought he would have received significantly less if he had been sacked.
The Treasury, which pumped £20bn into the crippled bank, was anxious to get new management in place.
But it now says it was misled by RBS's board at the time, which "gave the impression" that Sir Fred's pension was legally binding.
Gordon Brown said he discovered "in the last few days" that the package was "discretionary" and could have been blocked and he believed there was a possibility some of it could be retrieved in the courts.
They knew all along about this pension so all this synthetic anger now is just long after the horse has bolted
"The behaviour in the Royal Bank of Scotland, where very substantial additional pension awards were given, is something that makes me angry and will make the public of the country angry," he told BBC News.
He said the government was still appealing to Sir Fred, who was knighted for services to banking, to voluntarily waive some of his pension.
"When banks fail... the people who make the mistakes cannot and should not run off with entitlements and with additional discretionary payments."
He added: "This is unjustifiable, unacceptable and we are going to clean up the banks so that this doesn't happen again."
The government's appeal on Thursday to Sir Fred to hand his pension back voluntarily was angrily rejected by the former banker, who claimed it had been approved by Treasury Minister Lord Myners.
Sir Fred said he had already given up a significant part of his salary as a "gesture" when he was negotiating his departure from the bank.
In a letter to Lord Myners, he said: "I am told that the topic of my pension was specifically raised with you and you indicated that you were aware of my entitlement and that no further 'gestures' would be required".
I believe basically take it off him and let him sue in the courts
John Prescott, former deputy prime minister
In a letter to Sir Fred, released by the government, Lord Myners said the discussions he had with the former banker about the financial arrangements of his departure from RBS "did not amount to approval" of his pension payment.
He added: "I do not agree with your rationale for declining my request that you voluntarily reduce your pension."
"And indeed I hope that on reflection you will now share my clear view that the losses reported today (Thursday) by the bank which you ran until October cannot justify such a huge reward."
But shadow chancellor George Osborne, for the Conservatives, said the government's anger at the former bank chief's pension was "synthetic" because they knew about the package.
He said: "The problem for the government, and for Lord Myners who's a government minister, is that they knew all along about this pension so all this synthetic anger now is just long after the horse has bolted."
The shadow chancellor added: "It seems to me they're on the hook either way. They knew and they didn't stop it and that's what Fred Goodwin's saying."
He said the pension payout was "very symbolic" of what had gone wrong in the City and there was little chance of recovering the money in the courts, if the government decided to sue.
"I don't think the government's got much of a leg to stand on in the courts if they're going to take legal action. Let's hope they succeed, but it's doubtful."
Sir Fred is grilled about his pension by the Treasury Committee earlier this month
Mr Osborne's assessment was echoed by Lib Dem Treasury spokesman Vince Cable, who said: "It's clearly utterly grotesque that somebody should be paid this enormous sum of money."
Former deputy prime minister John Prescott said it had been an "extraordinary" decision to award Sir Fred the pension and called for the use of "all legal means" to claw it back.
He told BBC Radio 4's Today programme: "The taxpayer has rescued them, there is billions of pounds involved, he's not entitled to this kind of pension, whether who knew about it or not, you can investigate that later.
"I believe basically take it off him and let him sue in the courts."
He blamed the former board of RBS for the "extraordinary" decision to award the "obscene" level of Sir Fred's pension.
In October, Alistair Darling hailed the fact Sir Fred had waived his contractual entitlements and decided "to do the right thing".
There was no mention of the size of pension he was going to receive.
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