Britain vowed on Wednesday to support Ukraine to ensure military victory this year, as President Volodymyr Zelensky arrived in London on a rare foreign visit just weeks before the first anniversary of Russia's military campaign.
Zelensky, dressed in his usual green fatigues, held talks with Prime Minister Rishi Sunak and is due to meet King Charles III and address parliament on what is only his second overseas trip since the war began.
"The United Kingdom was one of the first to come to Ukraine's aid," Zelensky said on social media, adding he wanted to "personally thank" the British people.
The UK government said it would offer advanced training for Ukrainian fighter jet pilots and marines, as Western allies debate stepping up military aid for Kyiv against a feared new Russian offensive in the east.
After meeting Zelensky, Sunak told parliament the UK would continue "to support Ukraine to ensure decisive military victory on the battlefield, this year".
"(Russian President) Vladimir Putin's aggression cannot be seen in any way to have been successful, and that's why we have accelerated and increased our support militarily for Ukraine," Sunak said.
Ahead of the trip, President Joe Biden promised that the United States would support Ukraine "as long as it takes."
Britain announced a fresh round of sanctions targeting organisations relied on by the Russian military -- Putin remains defiant.
Updated maps of Russia have gone on sale in Moscow bookstores that include four annexed Ukrainian regions: Zaporizhzhia, Kherson, Lugansk and Donetsk. Putin regularly refers to them as "our historical lands".
Ahead of the February 24 anniversary of the start of Russia's military campaign, German Chancellor Olaf Scholz said it was clear that Moscow would not win and assured Ukraine its future was in the EU.
"Putin will not achieve his goals -- not on the battlefield and not through a dictated peace. That much, at least, is certain after a year of war," Scholz said in a speech to parliament.
"Ukraine belongs to Europe, its future lies in the European Union. And this promise holds true," Scholz said.
Ukraine's Foreign Minister Dmytro Kuleba said he had held a call with US Secretary of State Antony Blinken on the need for more sanctions and military aid ahead of the anniversary.
"Russia would be making a grave mistake if it thought anyone would get tired of fighting the evil it brings," Kuleba tweeted.
After the Downing Street talks and his speech in parliament's historic Westminster Hall, Zelensky was due to join Sunak on a visit to Ukrainian troops receiving military training in southwest England.
Britain says it has already trained 10,000 Ukrainian troops "to battle readiness" over the past six months and will train a further 20,000 this year.
The new UK training will "ensure pilots are able to fly sophisticated Nato-standard fighter jets in the future", the UK said, although Western countries have so far ruled out sending jets themselves.
Moscow said Tuesday that Russian forces were advancing towards Bakhmut and Vugledar -- two key centres of fighting in the eastern Donetsk region of Ukraine, now the flashpoint of the war.
On Tuesday, Denmark, Germany and the Netherlands promised that Ukraine would get at least 100 tanks in the "coming months", as the German defence minister visited Kyiv.
The three European governments also said training and support would be sent for the Leopard 1 tanks, ahead of the delivery of more advanced tanks in the future.
Last week, Sunak said sending the UK's Typhoon and F-35 fighter jets to Kyiv would require "months if not years" of training and that he was looking for the most effective way of helping Kyiv secure victory.
The United States has so far rejected any deliveries of F-16 warplanes to Ukraine, but other partners, including Poland, have shown themselves more open to the idea.
Germany recently gave the green light for Leopard battle tanks to be sent by allies but while Berlin has now moved, other nations that previously committed to sending the tanks now appear to be stalling.
Zelensky last week urged Western countries to speed up deliveries of weapons -- particularly long-range missiles -- so his forces can fend off Russian advances in the Donetsk region. (AFP)