Two sections of the carriers, instead of one, will be built in Scotland
The consortium building the UK's two new aircraft carriers has announced a 50% increase in the amount of construction work coming to Scotland.
The Aircraft Carrier Alliance said two major sections of each ship, instead of one, would now be built at BVT's yards at Govan and Scotstoun on the Clyde.
Both ships will be built in sections and assembled at Rosyth, Fife.
The revised build strategy is expected to sustain 4,000 jobs at Scottish yards until the middle of the next decade.
The new 65,000 tonne carriers will be the Royal Navy's largest vessels.
Changes to the delivery of the £4bn contract were announced on Monday.
The previous build strategy had planned for one of the sections of the carriers to be built at BAE Systems Submarine Solutions in Barrow.
But the Aircraft Carrier Alliance (ACA) said existing and future workloads there had led to a lack of capacity to take on the additional carrier work.
In agreement with the Ministry of Defence (MoD), ACA has now transferred the work to BVT's yards in Glasgow.
Geoff Searle, programme director for the Queen Elizabeth Class aircraft carriers, said: "The ACA has developed a cost effective and low risk build strategy that I am confident will deliver the two carriers in line with the MoD's requirements.
"It will also ensure that we retain the essential core skills in the UK maritime industry to deliver sovereign naval capability long into the future."
Tony Graham, head of capital ships at the MoD, said: "Alongside the developing build strategy, we are very pleased to announce additional shipbuilding work for the Queen Elizabeth Class carriers which further extends involvement across the UK.
"This provides greater certainty for our supplier base and keeps the project on a sure footing as we enter full-scale manufacture."
The SNP welcomed the increase in the amount of work awarded to Scotland.
The party's Westminster leader and defence spokesperson, Angus Robertson MP, said: "This is terrific news for the workforce in Glasgow and Rosyth and reinforces the reputation of Scottish yards as the best in the world.
"Shipbuilding plays an important role within Scotland's manufacturing base, and it is clear that the industry can have a confident future."
Labour accused the SNP of hypocrisy.
John Robertson MP said: "This is brilliant news for Glasgow and Scotland. It will mean more opportunities and more jobs for young people and older workers alike.
"It is totally hypocritical for the SNP to welcome a move like this, when their core policy - separating Scotland from the rest of the UK - would mean the death of these jobs."
He added: "Without the United Kingdom, there would be no defence work on the Clyde.
"The SNP should have the decency to be honest with people about what their plans would mean for Scots."
The Liberal Democrats reiterated that view. The party's defence spokesperson, Willie Rennie MP, said: "If the SNP had their way, these jobs would be heading down south.
"Independence would decimate the Clyde."
Last year, the government announced that there would be a delay on the carrier contracts following a review of MoD spending.
The vessels, HMS Queen Elizabeth and HMS Prince of Wales, were due to enter service in 2014 and 2016, but that will now be pushed back a year or two.
Contracts were signed in July 2008 and the work is expected to begin in spring 2009.