London will unveil a significant package of sanctions against Russia on Monday, which marks three years since the start of its war with Ukraine, UK Foreign Secretary David Lammy said on Sunday.

"This is also the time to turn the screws on (Vladimir) Putin's Russia," Lammy said in a statement.

"Tomorrow, I plan to announce the largest package of sanctions against Russia since the early days of the war - eroding their military machine and reducing revenues fuelling the fires of destruction in Ukraine," he added.

UK's decision to ramp up sanctions comes as US President Donald Trump has in recent weeks sought to sideline Kyiv and its European backers from talks with Russia on the future of the conflict.

"This is a critical moment in the history of Ukraine, Britain and all of Europe... Now is the time for Europe to double down on our support for Ukraine," said Lammy.

London has already imposed sanctions on 1,900 people and organisations with link's to Putin's government since the start of the war, as of January 2025.

Its sanctions target the Russian financial, aviation, military and energy sectors, including through bank asset freezes, travel bans, and trade restrictions.

EU countries last week agreed a new round of sanctions which includes a ban on imports of Russian aluminium set to be formally adopted on Monday.

In his statement, Lammy reiterated UK's military backing, which includes a pledge to provide US$3.78 billion annually to Kyiv and "being ready and willing to provide UK troops as part of peacekeeping forces if necessary". (AFP)