But some officers say it

Plan is to have 36 working in the south

Defence cuts have left the Royal Navy so short of engineers it has had to borrow some from the US Coast Guard.

This month, American servicemen will start work as engineering technicians on board Type 23 frigates on the south coast.

If it is a success, there will be a total of 36 Coast Guard personnel working in the positions in Portsmouth by the end of 2016.

The Royal Navy's Type 23 frigate HMS Westminster, moored in Portsmouth Naval Base

The navy says it is bringing the engineers to the city because of cuts to staff numbers in the government's 2010 Strategic Defence and Security Review.

Critics have called it a 'desperate move', saying it proves armed forces redundancies, which saw the loss of around 500 engineers in 2011, are a false economy.

Former naval officer Mike Critchley, the publisher of maritime book Warship World, said: 'Having to borrow engineers is hugely embarrassing and bringing them across is a desperate move.

'It is fortunate the US Coast Guard has excess personnel at the moment, after they have paid off some ships that were very manpower intensive.

'You can't just recruit guys off the street and train them - the Royal Navy is looking for experience.

'But I'm sure these guys will do a great job and keep ships at sea.'

The project will cost the navy £187,000 from April 2014 to April 2015, and the average pay for each engineer is £35,000.

First Class Cadet Holly Madden logs a reading in a ship engine room

Admiral Lord Alan West, a former head of the Royal Navy, said he thought the move was a sensible one.

He said: 'There is a national shortage of engineers in this country, and that is obviously going to affect the military as well.

'I have served with a lot of Americans and they fit in extremely well.

'This seems to me a good temporary measure but there does come a stage where we need more people in the navy.'

The Royal Navy said it is actively recruiting in all branches, including engineering.

It is not uncommon for servicemen and women from other nations to serve on board Royal Navy warships.

The First Sea Lord Admiral Sir George Zambellas welcomed the move, saying: 'The professional maritime partnership between the USA and the UK is one without equal.

'This latest initiative strengthens its authority further still.

'The Royal Navy already enjoys a highly successful collaboration with the US Coast Guard as we fight the war on drugs together.

'But this agreement takes our partnership to the next level - and beyond - and I warmly welcome that.

'It is quite true that the Royal Navy is under significant manpower pressure in key specialist skills to meet today's commitments.

'This is a recognised leadership and management challenge that is part and parcel of the Royal Navy's renaissance.

'We are working to meet that challenge, but also to chase the opportunities it offers, but I do not expect it to throw us off track.'

The trial partnership will begin this month when four personnel come over from America.

Another 16 will follow in 2015 and 16 more in 2016, bringing the total to 36.