The charging issue has proved very controversial

The jobs are to go over the next three years in a cost-cutting exercise.

Unions reacted angrily to the plans and called for an urgent meeting with the Sinn Fein minister.

However, Mr Murphy said he would propose a deferral of water reform plans when the new power-sharing executive meets on Thursday.

"The business plan for the water company was put in place on 1 April by direct rule ministers," he said.

"We'll want to look at all of that again. I'm not sure what scope there is for changing the structures that have been put in place, but we'll certainly want a review of how it proposes to carry out its business.

"It will be an issue for the executive as a whole, the whole issue of how water and sewerage services are proposed to be financed."

Water bills are have been deferred for a year

Union officials have said they want to begin negotiations to discuss the job cuts.

The current workforce of about 1,900 will be cut to 1,400 as part of a new strategic business plan.

Albert Mills from the Transport and General Workers Union called for an urgent meeting with Mr Murphy.

"It was the unions that led the fight against water charges and we have them deferred for a year now and we continue that fight against water charges," he said.

"We believe that we can certainly negotiate with the incoming minister because it is 500 jobs (lost) to the economy in Northern Ireland and we can ill afford to lose those jobs."

The job cuts will hit the firm's industrial division as well as engineering, administration and scientific divisions.

Katharine Bryan of Northern Ireland Water said: "It's not all bad news, it sounds a lot but, in fact, we have been able to transfer quite a significant number of people, almost 300, back to the civil service ahead of the new company being created.

"We backfilled some of those using temporary posts and at the same time recruiting to some of the new skills that we need."

Charges deferred

Northern Ireland water was set up on 1 April as a government-owned company.

It has a turnover of �400m and is investing �1m every day to update water and sewerage infrastructure which has suffered from chronic under-investment.

The government had intended that consumers would contribute to the company's income this year with the introduction of domestic water charges, but they have been put on hold.

The new assembly is now to look at the issue of water charges.