Boris Johnson has committed Britain to increasing defence spending to 2.5% of GDP by the end of the decade as Nato rises to the threat of Russian aggression.

The Prime Minister pledged the hike on Thursday after a Cabinet row over defence spending, and insisted that the “cost of freedom” is “always worth paying”.

As Mr Johnson met with Nato leaders in Madrid, the Government also set out a further £1 billion of funding to help Ukraine defeat Russian President Vladimir Putin’s invasion.

The UK is counting its support for Volodymyr Zelensky’s resistance within its defence spending, taking the current level to around 2.3% of gross domestic product (GDP) – a measure of the size of the economy.

The logical conclusion of the investments on which we propose to embark, these decisions, is that we’ll reach 2.5% of GDP on defence by the end of the decade

But, at a press conference at the Nato summit, Mr Johnson said it was necessary to “invest in the long term” while adapting to a “more dangerous and more competitive world”.

“The logical conclusion of the investments on which we propose to embark, these decisions, is that we’ll reach 2.5% of GDP on defence by the end of the decade,” he said.