ISTANBUL (Bloomberg) - Chancellor of the Exchequer Alistair Darling, seeking to avoid voter anger over executive pay as taxpayers support Britain's biggest banks, said bonuses should only be paid out if performance warrants it.

Britain's five biggest lenders agreed to sign up to Group of 20 (G-20) constraints on bonuses this week. The G-20 agreement demands banks don't allow bonuses to encourage risky trades or weaken their capital position while imposing no caps on pay.

"Bonuses need to be tied to performance," Mr. Darling on Saturday said in Istanbul, where he is meeting other G-7 finance ministers. "Having signed up to the agreement, we expect that banks, whatever they do come the bonus season, they stick to what they said."

While no UK banks revealed the size of their 2009 bonus pools, Goldman Sachs Group Inc. set aside a record $11.4 billion to pay compensation in the first six months of this year. The UK Treasury has extended 1.4 trillion ($2.2 trillion) of support to the economy including backing for Royal Bank of Scotland Group plc. and Lloyds Banking Group plc. and loan guarantees for other programmes.

Mr. Darling last week targeted what he calls "greed and recklessness" in the financial system, asking banks to curtail bonuses and said the rich will pay more in tax.

RBS CEO Stephen Hester on September 29 said he supported Mr. Darling's promise to curtail banker bonuses. RBS will be less affected by Mr. Darling's proposals than other banks because the lender adopted deferred bonuses and clawbacks last year, Mr. Hester said in an interview. Regulation of bonuses will benefit RBS by creating a "level playing field" among banks, he said.

Earlier this week, Mr. Darling met the heads of compensation committees from HSBC Holdings plc., Lloyds, Barclays plc., RBS and Standard Chartered plc. to get them to sign up to the principles.