Portsmouth shipbuilder VT said it was confident an agreement would be struck soon and that work would start within 12 months.

The news comes as the VT group announced a leap in pre-tax profits of 33 per cent, hailing Portsmouth a 'driving force' behind its success.

VT's chief executive Paul Lester said: 'We've had a very successful year and the dockyard has had a sizeable role in that.

'We need to see the contract for the carriers before we go ahead. I'm informed that is imminent and just a matter of weeks away.

'If all goes to plan, we can expect to start cutting metal for the carriers within 12 months.'

The supercarrier deal would see VT forming a hybrid company along with BAE Systems – BVT Surface Fleet Ltd.

VT already employs around 1,500 workers at the shipbuilding yards, and another 1,650 in support roles.

It completed the bow of a £1bn anti-air warfare ship at Portsmouth dockyard last week and said if the carriers deal went ahead, as hoped, it would be a huge boost to business and employment.

Mr Lester said: 'We'd probably be looking at taking on an extra 100 workers if this goes ahead. It would be great news for the city.

'Don't forget, these carriers would be based in Portsmouth, so that means jobs in support roles as well.'

Last year, Defence Secretary Des Browne announced that the supercarriers would be built. But as of yet no contract has been signed.

In addition to existing Royal Navy contracts, VT Group also has a current deal to build three ships each for Oman, and Trinidad and Tobago, at the dockyard, and is exploring further naval deals with Saudi Arabia, Greece, and Libya.