On Monday, Prime Minister Boris Johnson rejected calls for Britain to relax visa requirements for Ukrainian migrants escaping violence, saying that while the country was compassionate, it needed to keep an eye on who was coming in.

According to the United Nations, more than 1.5 million people have left Ukraine since Russia began bombing its neighbor, with hundreds of thousands more flowing into Poland, Romania, Slovakia, and other countries.

In response to accusations that Britain was not doing enough and was lagging behind its European neighbors in addressing the continent’s worst humanitarian catastrophe since World War II, Johnson stated:

“We are a very, very generous country. What we want though is control and we want to be able to check.” he told reporters. “I think it’s sensible given what’s going on in Ukraine to make sure that we have some basic ability to check who is coming in.”

The British government has been condemned by charities, opposition lawmakers and France after its insistence that refugees first acquire a visa meant some Ukrainians have been stuck in the French city of Calais, unable to enter Britain, and provoking a diplomatic row.

The European Union has agreed to grant temporary residency to Ukrainians fleeing the invasion and give them access to employment, social welfare and housing for up to three years.

Britain has announced visa schemes for those who have family in the country or a willing sponsor. Media reports at the weekend said Britain had only issued about 50 visas for Ukrainians so far, although Johnson disputed that without giving further details.

Labour Party leader Keir Starmer said: “There should be a simple route to sanctuary for those that are fleeing for their lives.”

“The Home office is in a complete mess about this, they keep changing the rules,” he told the BBC.

Scotland’s First Minister Nicola Sturgeon said Britain was not doing nearly enough. It should let refugees in and deal with the paperwork later, she said.

“Having fleeing the terror in Ukraine, spending hours and hours and hours on arduous journeys, then having to jump through bureaucratic hoops is unconscionable,” she told LBC radio.

Interior minister Priti Patel told the Sun newspaper she wanted to create a humanitarian route that would allow anyone from Ukraine to come to Britain. But Europe minister James Cleverly said he did not expect the existing requirements to change.

“We can’t do with ‘no questions asked’ because when people come to the UK we need to make sure they are supported,” he said.

Asked to clarify whether Patel was working on a third visa route, Britain’s interior ministry sent a statement detailing existing measures but did not rule out future changes.

“This is a rapidly moving and complex picture and as the situation develops we will continue to keep our support under constant review,” it said.