By James Marson 

The U.K. government announced its biggest increase in defense spending since the Cold War in a bid to secure its position as the U.S.'s main military ally in Europe after Brexit.

The U.K. will spend an additional 24.1 billion pounds, equivalent to $32 billion, over the next four years compared with last year's budget. That is GBP16.5 billion more than the government had already pledged, securing the U.K.'s rank as the second-highest spender on defense in the North Atlantic Treaty Organization behind the U.S.

"I have done this in the teeth of the pandemic amid every other demand on our resources because the defense of the realm and the safety of the British people must come first," Prime Minister Boris Johnson told Parliament on Thursday.

The U.K. shouldn't be "content to curl up on our island and leave the task to our friends," he said.

"Britain must be true to our history, to stand alongside our allies," he said. "To achieve this, we need to upgrade our capabilities across the board."

The announcement came as the U.K. approaches a year-end deadline for a deal on future relations with the European Union and prepares for a new U.S. administration under President-elect Joe Biden. German and French leaders, meanwhile, are squabbling in public over how independent Europe's defense policies should be from the U.S.

"The timing is excellent," said Julian Lindley-French, distinguished visiting research fellow at the National Defense University in Washington. "The French and Germans can say what they like. This sends a powerful message to the Americans that the one ally who can ease their burdens is the U.K."

The U.K. has long prided itself on its "special relationship" with the U.S., forged around close trade and military ties. But that relationship has been challenged by cuts to defense-spending plans over the past decade, and there is some concern in London that Brexit might shift Washington's attention to Paris and Berlin.

The U.S., stretched by the growth of China's military muscle and Russia's belligerence, has long pressed European allies to increase investment in their militaries. The call sharpened under President Trump, who berated allies such as Germany for spending well below the NATO target of 2% of gross domestic product. European officials say they expect Mr. Biden to maintain pressure even while softening the tone.

After two decades primarily focused on fighting counterinsurgency campaigns alongside the U.S. in Afghanistan and Iraq, the U.K. military is shifting its attention to the threat of adversaries such as China and Russia.

Mr. Johnson said the U.K. would focus on emerging technology that would revolutionize warfare, spending an extra GBP1.5 billion on military research and development. He announced a new agency dedicated to artificial intelligence, a new National Cyber Force and a Space Command.

The U.K. commissioned two aircraft carriers in the past three years and ordered an initial 48 F-35 stealth jet fighters with the aim of having one carrier strike group ready at all times starting in 2023. It is building new nuclear-powered ballistic missile submarines that carry the U.K.'s nuclear deterrent.

Those big-ticket investments have left the army in need of modernization, analysts say. The additional spending announced Thursday still leaves hard decisions on what equipment to upgrade or replace, including tanks, in a review of its security and foreign policy to be released at the start of next year.

Nevertheless, "this announcement has moved defense up the pecking order of public spending in the U.K., to be only exceeded by the National Health Service," said Malcolm Chalmers, deputy director-general of the Royal United Services Institute in London.

The leader of the opposition Labour Party, Keir Starmer, said he supported the government's plans, but questioned how they would be funded given the economic slump caused by the coronavirus pandemic.

The announcement caps a turbulent week for Mr. Johnson. His chief adviser resigned and Mr. Johnson appeared in Parliament via video link as he is self-isolating after a meeting with a lawmaker who later tested positive for coronavirus.

Mr. Johnson during the appearance touted the benefits of the additional spending for Scotland, where polls show support for leaving the U.K. is growing.

He said it would create 10,000 jobs a year across the U.K., including two Scottish shipbuilding hubs.

Write to James Marson at james.marson@wsj.com

(END) Dow Jones Newswires

November 19, 2020 12:33 ET (17:33 GMT)

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