Boris Johnson boasted a £16.5 billion boost to the UK defence budget will "reinforce the Union" and see a military rocket launched from a Scottish "space command" site in 2022.
Plans emerged ahead of a major defence statement with increased shipbuilding on the Clyde among the main proposals from the UK Government.
Johnson said the spending review, which follows a massive cut by the Tory government under David Cameron, would have benefits beyond defending the country.
"The returns of this investment will go far beyond our Armed Forces, creating thousands of jobs, reinforcing the Union and levelling up our country," he said.
The spending commitment will finance the Ministry of Defence’s current order of eight Type 26 and five Type 31 frigates on the Clyde, protecting vital shipbuilding jobs and the next generation of warship, the Type 32, which would also be built in the UK.
Johnson Space Command plan sparked comparison's with Donald Trump, who was mocked for his Space Force pledge in the US. The UK proposal could see the first rocket launched from Scotland in 2022. Several sites in the Highlands and Islands are competing to become spaceports.
The Mhoine peninsula in Sutherland hopes to be the site of one of the UK’s first spaceports if it wins approval from the Civil Aviation Authority.
Downing St said in a statement Scotland played a critical role in the UK’s defence. It said the country's "geographical position" makes it "an ideal home for half of the UK’s typhoon force and the Royal Navy’s entire submarine service, and to its people, who have always answered the call of duty to serve their country".
The statement added: "The projects announced by the Prime Minister today will, therefore, directly benefit the people of Scotland, bringing security and economic benefits for decades to come."
