Sir Keir Starmer has set up a team of experts to ensure British firms are complying with anti-Russian sanctions ahead of a visit by Volodymyr Zelensky to Downing Street.
The prime minister will welcome his Ukrainian counterpart and Nato secretary-general Mark Rutte on Thursday.
Following Russia’s full-scale invasion of its neighbour in 2022, Britain rolled out its most comprehensive set of sanctions against any major economy, with over £20bn worth of trade with Russia targeted.
The sanctions have deprived Russia of more than £300bn of funds since February 2022, the government has said.
In a bid to ramp up the pressure on Vladimir Putin’s regime, the Department for Business and Trade has established a new Office of Trade Sanctions Implementation (OTSI) to boost compliance with existing sanctions.
The body will issue guidance and user-friendly online tools to make complying with sanctions obligations easier, as well as threatening fines and other punishments for firms falling short.
The department said there has been “overwhelming support” from industry for sanctions rolled out so far, but warned: “For the minority that don’t comply, OTSI will have powers to publish information about sanctions breaches and impose civil monetary penalties.”
Business secretary Jonathan Reynolds said: “Sanctions are vital in defunding Putin’s illegal war and only by working hand in hand with business can we make them as effective as possible.
“This new unit will help ensure businesses comply with trade sanctions and take decisive enforcement action where needed so that, together with business, we can continue to exert maximum pressure on Putin’s regime.”
And Stephen Doughty, Sir Keir’s Europe minister, said: “This new government is resolutely committed to strengthening our sanctions regime, with robust enforcement and penalties for those who fail to comply.
“From Moscow to Tehran – kleptocrats, aggressors and the enablers who support and facilitate their wealth and malign actions should be on notice.
“OTSI will be instrumental in providing vital additional tools not only to help businesses comply with our sanctions, but also to deter and impose costs upon those seeking to breach them.”
The launch comes alongside new reporting obligations for firms in financial and legal services, who will now be mandated to report suspected sanctions breaches to OTSI.
The body’s power to enforce trade sanctions will complement those already possessed by HMRC, the government said.
Volodymyr Zelensky will visit Downing Street on Thursday as he tours European nations seeking support for Ukraine’s resistance against Russia.
The visit will be Mr Zelensky’s second trip to Number 10 since Sir Keir came to power after he addressed an extraordinary meeting of the cabinet in July.
The visit follows a summit meeting with south-eastern European countries in Croatia on Wednesday, during which he signed an agreement with Croatian prime minister Andrej Plenkovic on cooperation between the two countries’ defence industries.
The prime minister is expected to reiterate Britain’s ironclad support for Ukraine as it fends off Russia’s military. A spokesman for Sir Keir said it is a “critical point” in the country’s defence against Russian aggression, pointing to his remarks at the UN General Assembly.
At the gathering in September, Sir Keir said Russia is behind the “greatest violation of the [UN] charter in a generation”.