The UK stands “shoulder to shoulder” with Ukraine, Foreign Secretary James Cleverly said on Friday as he unveiled “hands-on support” for the country in its fight against Russia.
Mr Cleverly made the remarks on a visit to Ukraine, which is struggling to keep up with repairs to critical energy infrastructure caused by Russian missile strikes.
He said words alone "won't keep the lights on" or "defend against Russian missiles".
"The UK isn't just talking about Ukraine, we're providing concrete support for the defence of Ukraine," he tweeted on Friday.
Mr Cleverly announced that the UK will send 35 more emergency vehicles, including 24 ambulances and six armoured vehicles, to the country, plus a further £3 million ($3.63 million) for the rebuilding of local infrastructure, including schools and shelters, as well as additional funding to support survivors of sexual assault.
The package comes days after British Prime Minister Rishi Sunak visited Ukraine, where he met Ukraine’s President Volodymyr Zelenskyy and unveiled £50 million in defence aid, comprising 125 anti-aircraft guns and technology to counter Iranian-supplied drones, including dozens of radar and anti-drone electronic warfare systems.
Mr Cleverly, who will also hold a meeting with Mr Zelenskyy during his trip, said: "As winter sets in, Russia is continuing to try and break Ukrainian resolve through its brutal attacks on civilians, hospitals and energy infrastructure. Russia will fail.
"The UK stands shoulder to shoulder with Ukraine.
"I have today announced a package of hands-on support for our Ukrainian friends in their fight, from ambulances to crucial support for survivors of the sexual violence carried out by the Russian military.
"I've seen here first-hand how the UK's efforts are helping brave citizens to resist and rebuild. Our support will continue for as long as it takes for this remarkable country to recover."
The UK is also committing £5 million to a Ukraine-led initiative, delivered through the UN World Food Programme, to ship grain to countries most at risk of famine, including Yemen and Sudan.
The news comes as satellite images taken by Nasa show how Ukraine has become a dark patch on the globe at night because of the repeated Russian missile attacks.
The images, taken from space, show Ukraine in total darkness, surrounded by bright spots from other countries.
Russia has launched regular strikes since October with the aim of destroying the Ukrainian power grid.
The country’s president, Volodymyr Zelenskyy, told the Financial Times this week's strikes had created a situation not seen for 80 or 90 years ― "a country on the European continent where there was totally no light".
"The situation with electricity remains difficult in almost all regions," he said in his nightly address on Thursday.
"However, we are gradually moving away from blackouts ― every hour we return power to new consumers."
British military intelligence said Russia continues to struggle in its partial mobilisation, with many troops being compelled to serve in Ukraine with serious health problems.
A number of "common themes" are emerging in the experience of Moscow's mobilised reservists, according to the UK Ministry of Defence (MoD), with their deployment often characterised by inadequate training and personal equipment.
An MoD defence intelligence update suggests the Kremlin will be concerned that an increasing number of families are prepared to risk arrest by protesting against the conditions their relatives face at war.
Most mobilised reservists have previously served, it says, with "numerous examples" suggesting it is highly probable they are not having their medical status "adequately reviewed".
"Many are being compelled to serve with serious, chronic health conditions," the update states.
It also suggests there are likely to have been "particularly heavy casualties" among those committed to dig "ambitious trench systems" while under artillery fire around the city of Svatove, in the Luhansk region.
Meanwhile, reservists have been killed in "large numbers" in frontal assaults into well-established Ukrainian defensive zones in the Donetsk region, around the city of Bakhmut, it says.
"Two months after President [Vladimir] Putin announced a 'partial mobilisation', common themes are emerging in the experience of mobilised Russian reservists," the update states.