In show of support, British PM Johnson meets Ukraine's President Zelensky in Kyiv

President Volodymyr Zelensky met Prime Minister Boris Johnson, one of his staunchest backers, in Kyiv on Saturday, with the British leader using the visit to set out a new financial and military aid package for Ukraine.

Johnson is the latest foreign leader to visit Kyiv after Russian forces pulled back from the outskirts of the capital last week. The move caps weeks of lobbying by the British prime minister to meet Zelensky to underline their close ties.

"Today, I met my friend President Zelensky in Kyiv as a show of our unwavering support for the people of Ukraine," Johnson said on Twitter.

"We're setting out a new package of financial (and) military aid which is a testament of our commitment to his country's struggle against Russia's barbaric campaign."

Andriy Sybiha, deputy head of the Ukrainian president's office, said on Facebook that Johnson's visit had begun with a one-on-one meeting with Zelensky.

Volodymyr Zelensky (2R) speaks with Boris Johnson during their meeting in Kyiv. AFP

Zelensky's office published pictures showing the two men chatting across a table. Johnson met Zelenskiy "in a show of solidarity with the Ukrainian people," a Downing Street spokesperson said.

"They will discuss the UK's long-term support to Ukraine and the PM will set out a new package of financial and military aid," the spokesperson added.

On Zelensky's Telegram channel, Johnson was described as "one of the most principled opponents of the Russian invasion, a leader in putting sanctions on Russia and providing defensive support to Ukraine."

His chief of staff, Andriy Yermak, said Johnson was one of Ukraine's "true friends."

"Since the very beginning of the Russian aggression Zelensky has been in touch with him," Yermak said on Twitter.

"Thanks Boris Johnson for decisive stance and helping Ukraine in the time of utmost need. Thanks for all the support and weapons the UK is providing us," he added.

Johnson's visit to the Ukrainian capital was not announced in advance, and comes as Russia is amassing troops in the east of the country.

"The UK will send more defensive weapons to Ukraine and will work with G7 partners to target every pillar of the Russian economy to ensure Putin fails," Johnson tweeted earlier on Saturday.

Agencies