Jeremy Hunt has defended plans to cut public sector jobs to boost defense spending and aid to Ukraine during a surprise trip to Kiev.
The Chancellor said cutting public services would “cost much less” than allowing Russia to succeed.
The government has pledged to increase UK military spending to 2.5% of national income by 2030.
Mr Hunt confirmed the increase will cost an additional £20 billion, which unions say will be funded by cutting 70,000 jobs.
Downing Street said the plans would be funded by existing commitments to reduce the number of civil servants to pre-Covid levels and to give the Ministry of Defense (MoD) a share of a previously announced increase in government research spending.
The Public and Commercial Services Union said cutting public sector jobs to fund higher defense spending would lead to longer waiting lists for new passports, driving tests and licenses.
The announcement comes after Prime Minister Rishi Sunak confirmed that the UK will provide an additional £500 million for Ukraine this year, on top of the £2.5 billion already committed.
Mr Sunak added that the UK could continue to provide Ukraine with “at least the current level of military support for each year required”.
Speaking in Kiev before a meeting with President Volodymyr Zelensky, Mr Hunt said he hoped the funding increase would represent “a turning point in this war”.
“We believe other European countries will follow us and that will signal to Putin that he will not succeed,” Mr Hunt said.
“The UK has a special role” in supporting Ukraine’s war effort because “we have the largest defense budget in Europe,” he added.
“I am here because if we want to restore peace in Europe, we must ensure that Putin does not succeed in his evil war of aggression here in Ukraine,” he said.
On cutting public services to fund defense spending and Ukraine aid, he said: “This is a decision, but the decision we are making is to invest in European security and defense.”
“And if we stop Putin from doing what he is trying to do in Ukraine, it will end up costing all of us a lot less.”
“I think it makes sense to reduce the public service to its pre-Covid size and I am confident that we can achieve this through more efficient delivery of public services.”
Mr Hunt confirmed that spending, which will gradually increase over the next six years, would be £20 billion more than if spending remained at its current level of 2.3% of GDP.
The additional funding will also help fund ongoing Ministry of Defense programs such as the ordering of new naval frigates, the development of a new fighter aircraft and the modernization of the UK’s nuclear weapons systems.
These programs are proving very costly and the Defense Department is struggling to make ends meet with its existing resources.
Labour’s shadow defense secretary John Healey said on Tuesday his party wanted to “see a fully funded plan” to reach that level.
But the Tories have “shown time and time again that they cannot be trusted in defense,” he added.
He said Labor would review resources for the armed forces within a year of taking office if it wins the general election later this year.