Leaders of Christian denominations in London issued a joint appeal after meeting at the capital’s Ukrainian Catholic cathedral, expressing concern at Europe’s “greatest humanitarian crisis” since World War II.

“How can mothers with young children, the elderly and the disabled, who have travelled a thousand miles, be expected to complete online application forms in a language foreign to them?” they said.

“Times of war require swift action and flexibility, the easing of normal procedures, and the removal of complex bureaucratic obstacles that can easily turn hope into despair and resignation.”

Ukraine’s ambassador to London, Vadym Prystaiko, earlier told a parliamentary committee there had always been “bureaucratic hassles” when applying for a UK visa.

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Ukrainian women and children flee war as men stay and fight

Ukrainian women and children flee war as men stay and fight

While he got his on time before he took up his post, his wife did not, he told the House of Commons’ Home Affairs Committee.

The Board of Deputies of British Jews, meanwhile, said it was concerned about a 90-year-old Holocaust and 1930s famine survivor from Ukraine who was caught up in visa delays in Poland.

The Jewish News reported that the family of Kateryna Razumenko were desperately trying to get her to London with her 62-year-old disabled daughter, Larysa.

But after fleeing bombardment in Kharkiv, they were stuck in limbo in temporary accommodation in Poland, the newspaper said.

Marie van der Zyl, president of the Board of Deputies of British Jews, called on the government to “substantially increase capacity” and speed up the process.

Home Secretary Priti Patel and her department have been accused of forcing Ukrainian refugees to jump through hoops to secure visas to travel to the UK.

Prime Minister Boris Johnson told parliament the visa checks were needed because the Kremlin had singled out Britain over its stance on the crisis in Ukraine.

“There are some people who would like to dispense with checks altogether and simply to wave people through. I do think that is irresponsible,” he said. “We are going to be as generous as we can possibly be, but we must have checks.”

Hundreds have travelled to the Channel port of Calais in the hope of crossing to join family in Britain, only to have been turned away because of a lack of travel documents.

The UK response has earned unfavourable comparisons with the European Union, which is allowing Ukrainians three-year residency rights without applying for a visa.

So far, Britain has granted 957 visas, according to Downing Street.

Prystaiko suggested that with 50,000 to 60,000 Ukrainians in the UK, some 100,000 of their relatives may seek to join them.

The former head of the British Army, Richard Dannatt, told Times Radio the UK position was a “national embarrassment” and “out of line” with the rest of Europe.

“It’s an own-goal of some significance,” he added.

The Spectator magazine, formerly edited by Johnson when he was a journalist, said the UK was “failing Ukraine’s refugees”.

It carried a front-page cartoon headlined “Border farce”, in a mocking pun on Britain’s Border Force agency.

Johnson – who made border control a key plank of his Brexit campaign to leave the EU – insists Britain needs to carry out proper security checks before issuing visas.

Behrens said refugees who have fled the fighting “want to be safe and reunited with their family members in the UK as soon as possible”.

“In this horrendous situation swift action is needed to make sure the process of getting a visa is simple, accessible and quick. Lives depend on it.”

Patel caused confusion this week by insisting an emergency visa application centre had been set up in Calais, only to backtrack and say it was not operational.

The Home Office then confirmed the centre would be set up 110km (70 miles) from Calais in Lille. A spokesperson said it will open on Thursday.

The decision to locate it in Lille was “in light of the risks from criminals actively operating in the area around Calais”, the spokesperson added.

Additional reporting by Reuters