Public sector employees have urged MPs to back them in their campaign against large scale job cuts.

Members of the Public and Commercial Services (PCS) union were lobbying parliament on Wednesday, two days after Gordon Brown unveiled his plans for over 100,000 job cuts.

The chancellor has said the efficiency drive will release over £21 billion for front line services, but the union argues that delivery will be undermined by the loss of so many jobs.

PCS members are also highlighting the issue of "endemic low pay levels", noting that 90,000 staff employed by the Department for Work and Pensions (DWP) are earning less than £15,000.

General secretary Mark Serwotka said he was "very disappointed and angry at the way this has been handled".

"We will oppose mass job cuts and industrial action may form part of our campaign," he added.

The union insists its members "deliver vital front line public services to some of the most vulnerable sections of society including pensioners, children, the unemployed, people with disabilities and homeless people".

And it warns that the government's proposals for job cuts at the DWP "will have a detrimental impact on service delivery and the public".

"This level of assault on the civil service is unprecedented and as a consequence staff morale has taken a hammering," said PCS national officer Keith Wylie.

"I've received hundreds of calls from staff who do not know their future and the lobby will give them the chance to voice their opposition to this government's cruel attack on the valuable work that they do everyday."

While experts have raised doubts about whether ministers will be able to achieve the scale of efficiency savings outlined in the latest spending review, much of the planned increase in spending is tied to cutting office running costs.

Without the increased efficiency, plans to fund other services could be facing trouble.

And the chancellor has insisted that the cuts will be delivered without reducing service provision.

"New technology enables things that used to be done manually to be done electronically," Brown told the BBC on Tuesday.