The UK government’s refugee policy, however, has come under scrutiny after it was confirmed over the weekend that about 50 Ukrainians had been granted visas, the BBC reported.
Johnson said the UK would be “very generous” to refugees but would not let people in without any checks.
It comes amid calls to do more as Russia’s invasion of Ukraine continues.
Johnson will discuss further sanctions against Russia with Canadian Prime Minister Justin Trudeau and Dutch Prime Minister Mark Rutte during their talks.
Later, he is expected to join a call with US President Joe Biden, French President Emmanuel Macron and German Chancellor Olaf Scholz.
During a visit to an RAF station with his fellow leaders, Johnson said he was not sure about the accuracy of the 50 visas figure but said the UK was “processing thousands”.
The government has so far announced two main schemes for people fleeing Ukraine to come to the UK — one which allows family members of people settled in the UK to join them and the other which allows organisations to sponsor a Ukrainian’s entry.
He said the schemes were “very generous” but said Putin was “doubling down on his aggression” and was attacking “in a pretty indiscriminate way” which would displace huge waves of people – adding that “we’re going to have to respond to that”.
Asked whether the government was considering a third option for refugees, Johnson did not answer directly but said the UK would not create a system “without any checks or any controls at all”.
Home Office sources have said they are in the early stages of exploring a scheme to provide humanitarian access to people fleeing the conflict.