UPDATED, 1.15pm: Prime Minister Tony Abbott today promised 2500 ongoing shipbuilding jobs “focused on Adelaide” from 2020 onwards.

However, he said naval shipbuilding jobs in Adelaide would drop from about 2000 to 1000 before bouncing back to 2500 once the future frigate project begins in 2020.

In Adelaide for a Cabinet meeting today, Abbott told ABC 891 this morning that two major defence construction projects – offshore patrol vessels and new naval frigates – would be brought forward.

“It’s a terrific announcement for Adelaide,” he said.

“We will have up to 2500 shipbuilding jobs safe for all time, focused on Adelaide, as a result of the decisions the Government is now taking.”

He said the future frigate project was the “first prize” for South Australia, and future submarine jobs would be the next “prize” for the state.

“The frigates are coming as the first prize and one way or another the subs will be coming as a further prize,” he said.

“So first prize, frigates, and further prize, subs. Because whatever the competitive evaluation process ultimately turns up there will certainly be more submarine jobs in South Australia.

“But what the Government will announce today is all about addressing the valley of death which the former Labor government’s failure to make decisions left us, and it will be about ensuring that there are 2500 ongoing surface naval shipbuilding jobs centred here in Adelaide.”

Abbott said no-one should assume the submarine build wouldn’t happen in Adelaide.

“As you might remember the competitive evaluation for the subs – and we’ve got this process happening with Japan, France and Germany – the competitive evaluation process asks our partners to give us a price for local build, hybrid build and offshore build.

“And when we get all of those figures in that’s when we’ll make a final decision.”

Following the Cabinet meeting in Adelaide this afternoon, Abbott confirmed there would be a $40 billion naval shipbuilding program based in South Australia that would provide a “continuous build”.

Defence Minister Kevin Andrews said the plan would end “boom and bust” in the defence industry.

“Over the next 25 years, we will be effectively rebuilding the naval fleet in Australia,” he said.

He said the final details of costs of the program and other infrastructure needs would be detailed in the forthcoming Defence White Paper.

Industry Minister Ian Macfarlane said that while “one door” had closed in South Australia with the impending end of the automotive industry, defence offered a bigger opportunity for local industry.

Earlier, Premier Jay Weatherill, who said he had been briefed by the Prime Minister on the plan, welcomed the announcement.

“This is a big win for South Australia,” he told ABC radio.

“We’ve been pursuing a continuous ship build program which really is at the heart of getting a sustainable shipbuilding industry and we’ll really overcome a number of these issues that we’ve seen with the stop-start nature of our shipbuilding industry. So it’s a fantastic piece of news for South Australia.”

Jay Weatherill and Tony Abbott have dropped the political hostility. AAP image

Weatherill said that while Abbott’s jobs figure related to all naval shipbuilding, he believed most of those jobs would be in Adelaide.

“Principally it’s South Australia, there’s no doubt about that,” he said. “Today’s announcement is an unalloyed win for South Australia, there is no other way of looking at it and we just need to build on that and do other things.”

Weatherill also seemed more confident about the future submarines project, uncertainty about which he has used to bludgeon the Abbott Government for months.

When asked specifically about the submarines, he said: “We had very constructive discussions about a series of additional projects, not just defence projects. The question of submarines always arises whenever we have a discussion but also other infrastructure projects. I hope that we’ll be seeing further positive announcements for South Australia in the coming weeks and months ahead.”

Reflecting the continued thaw in relations between the Weatherill and Abbott governments, Abbott also had some praise for the state Labor Government.

“There was I think some bad blood early, but I’m pleased to say in recent months it’s been much better,” Abbott told FIVEaa.

“And it hasn’t just been myself and the Premier, certainly Christopher Pyne and Jay Weatherill have been having quite a few conversations together. I think it’s really important for all our leaders to have a constructive relationship regardless of party politics.

“You might recollect a couple of weeks back we had a COAG leaders’ retreat, and the really good thing about that was all of the heads of government, we took our party political hats off, we laid down our usual weapons, we had a very, very constructive discussion. And I’ve got to say Jay Weatherill was a leading part of that discussion, had a lot of very interesting things to say about a whole lot of things including more efficient delivery of services, a more effective and fairer tax system, and I think I can work with Jay Weatherill.

“What I think you’ll see in coming weeks is further evidence of the Commonwealth and the State governments working together for the benefit of South Australians.”