UK shipyards: Five frigates at centre of new strategy
A new national shipbuilding strategy intended to benefit UK shipyards is being unveiled by Defence Secretary Sir Michael Fallon.
The government plans to buy at least five frigates, and share the work between shipyards around the UK.
The first batch of new Type 31e frigates will bolster a depleted Royal Navy fleet, but it is hoped future ships will be bought by foreign navies.
It comes as the Ministry of Defence aims to save billions of pounds.
The new frigates would be built across different shipyards, but assembled at a central site, and ready for service by 2023.
Their cost would be capped at £250m each.
Analysis: Will the plan work?
By Jonathan Beale, BBC defence correspondent
The strategy has been called "ambitious" and with reason.
Will there be enough work to sustain several shipyards in the UK? Will there really be demand from abroad for British-designed warships?
And can you really build a frigate for just £250m? Defence doesn't have a great record of keeping costs under control.
And that highlights a larger problem. The MoD's budget is once again in crisis. It's equipment programme has become more expensive because of a fall in the pound.
It still has to find tens of billions of pounds in "efficiency savings". And all three services are struggling to recruit and retain key personnel.
Defence Secretary Sir Michael Fallon boasts of a growing defence budget. But the sums still don't add up.
To balance the books, the MoD will need to make another round of painful defence cuts.
Sir Michael told BBC Breakfast this was a "huge opportunity" for UK shipyards which could bid for these "big contracts" next year, with building expected to start the following year.
"It's a great day for the Royal Navy."
The navy currently uses Type 23 frigates, which would be slowly phased out, added Sir Michael.
They are to be replaced by eight Type 26 frigates, which are being built in Glasgow, and five of the smaller Type 31e frigates.
He acknowledged previous warships had been over-budget and delivered late.
But he insisted that the new approach of fixing the price at the start, as recommended by industrialist Sir John Parker in his 2016 shipbuilding review, would allow them to take advantage of the "renaissance" in shipbuilding.
"We have to get back to making things," he told BBC Radio 4's Today programme.
He said the defence budget would increase from £36bn this year to £37bn next year.
"I'm determined our armed forces will have the new equipment they need," he added.
Scottish National Party defence spokesman Stewart McDonald said the plans had "nothing to do with ambition".
"It is all about squeezing costs to the bone and cutting corners, and still leaves real uncertainties for the future for workers at Scottish shipyards and the communities that depend on them."
GMB, the union for workers in the shipbuilding industry, said it would watch the government closely to see whether it "backs its warm words with deeds" to protect the UK's shipbuilding future.
"Without a clear commitment from government, it will be foreign competitors who will benefit from vital work that should be taking place in UK yards," GMB national officer Ross Murdoch warned.