Britain's prime minister on Friday made his second visit to Kyiv in just over two months, offering Kyiv a military training programme as President Volodymyr Zelensky hailed Britain's "resolute" support.
"Many days of this war have proved that Great Britain's support for Ukraine is firm and resolute. Glad to see our country's great friend Boris Johnson in Kyiv again," Zelensky wrote on Telegram with a video of him greeting the British leader at the presidential palace.
"Mr President, Volodymyr, it is good to be in Kyiv again," wrote Johnson on his official Twitter account.
The visit came a day after the European Union's most powerful heads of state embraced Ukraine's bid to be accepted as a candidate for EU membership, nearly four months into the Russian invasion.
It followed European Commission backing for Kyiv being granted EU candidacy status in a move likely to be formalised at an EU leaders' summit on June 23-24.
Such a move would be a potent symbol of support for Kyiv in its conflict with Russia.
Johnson became the first leader of a G7 country to visit Kyiv on April 9, two weeks after Russian troops had been driven back from the suburbs of the capital.
He was filmed on a walkabout through Kyiv's deserted streets with Zelensky in a move acclaimed by Ukrainians for his show of solidarity, prompting the president to say Britain's support for Ukraine would "remain forever in history".
- 'War crime' -
Beset by problems at home and facing record-low opinion polls from British voters, Johnson last week narrowly survived a vote of no confidence by his own MPs over alleged parties at Downing Street while the country was under lockdown during the coronavirus pandemic.
On Friday, Johnson's Downing Street office said Britain stood ready to offer Zelensky a major new training programme with the potential to train 10,000 new and existing Ukrainian soldiers every 120 days.
London claimed that the move would "fundamentally change the equation of the war, ensuring the Armed Forces of Ukraine have the resilience they need to be victorious in their fight for enduring peace".
The previous Operation Orbital saw the UK train more than 22,000 Ukrainian personnel from 2015 until this year's invasion.
The British leader said it was "great to be back" in Kyiv, noting that "life is coming back to the streets, to the cafes, to the restaurants.
"But we've got to face the fact that only a couple of hours away a barbaric assault continues on entirely innocent people," he added.
He accused Russia of deliberately targeting civilians in "what is unquestionably a war crime" but said that Ukraine's resistance was hampering Moscow's plans.
- Pressure -
Britain's highest-ranking military officer, Chief of Defence Staff Admiral Tony Radakin, earlier on Friday said Russia had "strategically lost" in Ukraine.
"President Putin has used about 25 percent of his army's power to gain a tiny amount of territory and 50,000 people either dead or injured.
"Russia is failing," he said in an interview.
In Kyiv, Johnson said Russian troops were "under acute pressure themselves and they are taking heavy casualties".
"Their expenditure of munitions, of shells and other weaponry, is colossal and after 114 days of attack on Ukraine, they have still not achieved the objectives they set out for the first week."
Britain would work with Ukraine "to liberate the grain... that is being held hostage right now by Putin, depriving people around the world of the food that they need," he added.
"We will continue... to provide the military equipment that you need and now of course the training that may be necessary to go with that... so that you, the Ukrainian people... will be able to do what I believe Ukrainians yearn to do: and that is to expel the aggressor from Ukraine," he added.