Boris Johnson has called for Britain to increase its defence spending to 3 per cent in order to help guarantee Europe’s security against Russian aggression.

The former prime minister was speaking to The Telegraph during a visit to Kyiv on Monday to mark the third anniversary of Russia’s invasion.

His trip comes ahead of Sir Keir Starmer travelling to Washington later this week to present Donald Trump with proposals that include Britain boosting its defence spending

But Mr Johnson said existing plans to increase spending from 2.3 per cent to 2.5 per cent would still still mean Britain is tens of billions below requirements, and he urged it to be upped to 3 per cent by 2030.

He said that a 3 per cent target would help convince Mr Trump that Europe was serious about sharing more of the region’s defence spending burden, amid concerns that the new administration in the White House is not willing to come to the old Continent’s defence.

“We should get to 3 per cent by 2030,” Mr Johnson said. “2.5 per cent is not enough.”

The former prime minister made the comments in a wide-ranging interview in which he sought to play peacemaker between Washington and Kyiv over Mr Trump’s recent comments that Ukraine provoked its war with Russia. Mr Johnson described the comments as an insult to Ukraine’s war dead – and also said that Kyiv had a “moral case” to build its own nuclear weapon if the West continued to let it down.

The interview can be heard in full on the new edition of the Telegraph podcast Ukraine: The Latest, which will also be available in Ukrainian and Russian.