The Prime Minister will meet with Ukrainian president Volodymyr Zelenskyon on Tuesday, and has committed money from the UK’s Good Governance Fund to help “support stable governance and energy independence”.
As well as supporting transparency and anti-corruption initiatives, some of the £88 million announced will go towards efforts to reduce Ukraine’s reliance on Russian energy supplies.
Mr Johnson said: “It is the right of every Ukrainian to determine how they are governed. As a friend and a democratic partner, the UK will continue to uphold Ukraine’s sovereignty in the face of those who seek to destroy it.
“We urge Russia to step back and engage in dialogue to find a diplomatic resolution and avoid further bloodshed.”
It comes as more than 100,000 Russian troops were amassed on the Ukrainian border, and Russia’ President Vladimir Putin has so far resisted calls to deescalate tensions.
Downing Street said that since 2015, British Armed Forces had trained more than 22,000 Ukrainian troops, and that the UK also defends the rule of law in the country by helping to reduce corruption.
But Mr Johnson, on his visit to Kyiv, is expected to discuss a “full range of strategic UK support” on offer.
Earlier, Foreign Secretary Liz Truss announced plans for legislation with new powers to sanction individuals and businesses linked to the Russian state, in light of the aggression in Ukraine.
“We will be able to target any company that is linked to the Russian state, engages in business of economic significance to the Russian state or operates in a sector of strategic significance to the Russian state,” she told MPs.
“This will be the toughest sanction regime against Russia we have ever had and it is the most radical departure in approach since leaving the EU. Those in and around the Kremlin will have nowhere to hide.”
Ms Truss was due to join the PM on the trip, but tested positive for coronavirus on Monday evening.
The UK is also expected to bolster military presence in eastern Europe as part of Nato’s efforts to secure the region.
But British and Nato combat forces are not expected to be deployed in Ukraine, which is not a member of the alliance.
Around 100 British personnel are involved in a training mission in the country.
Mr Putin has denied he is planning an attack but is demanding guarantees Ukraine will never join Nato, while calling on the Western alliance to draw back its forces in eastern Europe.