Vladimir Putin and his allies should carry the burden of funding the reconstruction of Ukraine after the war, Foreign Secretary James Cleverly has said.
Although there was a role for international allies and the private sector in rebuilding Ukraine's economy, Mr Cleverly said a significant amount of the burden - "perhaps even the majority" - should fall on Russians involved in the invasion.
The UK is hosting a major conference on Ukraine's recovery this week and Mr Cleverly discussed the situation with his US counterpart Antony Blinken on Tuesday.
The government has set out plans for new laws which will enable sanctions targeted at Russian oligarchs, members of the Russian President's inner circle and those involved in his war machine to remain in place until reparations are made.
He said it "follows that simple premise that you break it, you bought it".
Mr Cleverly added: "There is a very strong principle of natural justice, whereby a significant, perhaps even the majority, burden for the rebuilding should sit on the shoulders of those who have been responsible for funding or facilitated this brutal, full-scale invasion of Ukraine."
Ahead of the Ukraine Recovery Conference in London, the foreign secretary said private firms needed assurances their investments in rebuilding the country were "safe" and the Kyiv administration also needed to implement reforms.
He said: "This week is very much about encouraging the private sector to invest in Ukraine's rebuilding and recovery.
"We recognise that means we need to demonstrate that those investments will be effective and that they will be safe.
"That means the ongoing assurance that the Ukrainians seek that they will not be reinvaded once they have successfully regained their territory, their further integration into the Euro-Atlantic institutions and European institutions that they understandably aspire to."
Ukraine wants to join Nato and benefit from the security guarantee that comes with membership of the alliance.
Both Mr Cleverly and Mr Blinken spoke of the need for Kyiv to implement reforms so that it had a strong, prosperous democracy.
Mr Blinken said international allies would help Ukraine have "the strongest possible democracy which is actually necessary to achieve a thriving economy and for reconstruction".
"If Ukraine is going to attract the investment it needs, not just from government, not just from the international financial institutions but from the private sector, it has to build the best possible environment to attract that investment," he said during a visit to London.
Mr Blinken said he would announce a new "robust US assistance package" for Ukraine on Wednesday.
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