President Volodymyr Zelenskyy spoke in an online event earlier this morning and was quick to praise Mr Johnson.
He said: "I am very happy about this. Boris Johnson is a true friend of Ukraine.
“I regard him as our ally, and Great Britain as a great ally.”
Speaking through a translator, Mr Zelenskyy also said: “Boris is supporting us. Boris is very concrete in supporting Ukraine.
“I do not know who was responsible for this decision yesterday but I’m glad we have not lost a very important ally. This is great news. That is all I can say.”
His comments at the event, hosted by the Financial Times, fall in the wake of Mr Johnson's confidence vote, in which he received a nod of support from 59 percent of Tory MPs.
An official spokesman for Mr Johnson said: "The Prime Minister enjoys a very close relationship with President Zelenskyy.
“He believes it is vital to how the UK is able to adapt and support Ukraine in this fast-moving situation.”
He added how the relationship between the UK and Ukraine “benefits both the Ukrainian people in being able to be responsive to the support they need but also to ensure the UK is at the forefront of providing that support”.
In a Cabinet meeting earlier today, Mr Johnson reiterated his support for the war-torn country.
The Prime Minister added how it was vital for Mr Zelenskyy not to be pressured into accepting a bad peace deal and that the world must avoid any outcome where Russian President Vladimir Putin’s aggression in any way pays off.
Foreign Secretary Liz Truss told ministers that Ukrainians had achieved some recent success but Russia was also making slow advances.
Ms Truss said the UK would continue its support with further sanctions in the pipeline.
Ahead of the confidence vote on Monday, the Prime Minister uploaded an image of himself on the phone to Mr Zelenskyy.
“President (Zelenskyy) just updated me on the ongoing battle against Russian aggression in the Donbas,” Mr Johnson tweeted.
“It’s clear the Ukrainian people will not bow to Russian brutality. We’re unwavering in our mission of ensuring Ukraine is defended and supported for the long-term.”
In another tweet, he also posted about rocket launchers being sent to Ukraine.
Ukrainian President Volodymyr Zelenskyy praised Boris Johnson for his victory in his leadership challenge
Matt Dunham
Prime Minister Boris Johnson chairs a Cabinet meeting today
Leon Neal
