Mr Brown defended Labour's record on the NHS

The prime minister-in-waiting has been criticised for giving a 2.5% pay award in two stages.

He was met with shouts of "rubbish" as he told the Unite conference that by November, there would be a 5% rise for the average nurse.

Mr Brown said he had to stagger the award to prevent inflation and interest rates rising further.

The chancellor, who will succeed Tony Blair as prime minister on 27 June, was speaking at the Unite conference on Monday.

'Breaking point'

One member of the audience told him NHS staff were at "breaking point" by the pay awards, "continual reorganisations", redundancies and privatisations.

She asked why, when an independent pay review body had recommended a 2.5% rise, the Treasury had decided to stagger it over two stages.

Unions say this reduces its value to 1.9% and have threatened to strike.

Like it or not, the choice in the NHS is between more jobs or more pay Gordon Brown MPs back calls for nurse pay rise

Mr Brown defended Labour's record on the NHS, saying they had doubled investment, employed thousands more staff, built more than 100 new hospitals and improved rates of heart and cataract operations.

"We have put more money in and I have got to be honest, we have increased pay as well," Mr Brown said.

"For many people there has been a 50% increase in pay over the last 10 years."

Inflation fears

Mr Brown told the audience he had been worried that inflation would start to get out of control, as it went up to 4.3% in the US, nearly 3.5% in the G7 countries and above 3% in Britain.

"Like it or not, the choice in the NHS is between more jobs or more pay. We have got more jobs, I want to pay people more but I have got to get to a situation where I can control inflation first and then we can actually invest in the future."

But he was met with shouts when he said, taking into account the pay rise and the Agenda for Change pay system introduced in 2004, the average nurse would benefit from a 4% rise from April and 5% from November.

"I'm very happy to talk to the people here afterwards, about what we can do in future years," he added.

"I believe that where people are low paid, they should get a better deal."

Both Tory leader David Cameron and Lib Dem leader Sir Menzies Campbell have backed nurses' call to get the 2.5% rise immediately.