LONDON (Reuters) - Britain announced its biggest military spending increase since the Cold War on Thursday, pledging to end the “era of retreat” as it seeks a post-Brexit role in a world Prime Minister Boris Johnson warned was more perilous than for decades.Johnson said the extra spending reflected the need to upgrade military capabilities even as the COVID-19 pandemic pummels the economy and strains public finances. He outlined plans for a new space command, an artificial intelligence agency and said the navy would be restored as Europe’s most powerful. Outlining the first conclusions from a big review of foreign policy and defence, he announced an extra 16.5 billion pounds ($22 billion) for the military over the next four years. The defence budget is now just under 42 billion pounds a year. “The era of cutting our defence budget must end, and it ends now,” Johnson told parliament by video link from his Downing Street office, where he is isolating after contact with someone who tested positive for COVID-19. “I have done this in the teeth of the pandemic, amid every other demand on our resources, because the defence of the realm and the safety of the British people must come first.”Britain was the main battlefield ally of the United States in Iraq and Afghanistan and, alongside France, the principal military power in the European Union. But its 2016 vote to leave the EU has made its global role uncertain at a time when China is rising and President Donald Trump has cast doubt on U.S. support for traditional allies. Malcolm Chalmers, deputy director-general at the Royal United Services Institute for Defence and Security Studies think tank, said the funding means Britain will retain its position as a middle-rank military power alongside nations such as France, Germany and Japan, but well behind the United States and China. “This is the government saying just because we have Brexit it doesn’t mean we are not a strong alliance player and punching above our weight as we have done for decades,” he said.