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British Foreign Secretary Liz Truss will tell the UN Human Rights Council that Russia must be isolated on the international stage in punishment for killing “Ukrainians indiscriminately”.
Ms Truss is due to address a meeting of the council in Geneva on Tuesday after the “unprovoked Russian invasion of Ukraine”, the Foreign Office said.
She is expected to tell the council that Russian President Vladimir Putin has “blood on his hands” and that he has broken international law by sending troops into Ukraine.
The comments are due to be made 24 hours after Moscow suggested it had put its Russian nuclear deterrent on high alert in response to unspecified comments made by Ms Truss.
While in Switzerland, she is also due to meet other foreign ministers and the UN High Commissioner for Refugees, Filippo Grandi.
Ms Truss is expected to tell the UN council: “The consequences of Vladimir Putin’s unjustified aggression are horrific. Russian troops are laying siege to once peaceful cities.
“Tanks are tearing through towns while missiles barrage homes and hospitals. There is blood on his hands, not just of innocent Ukrainians but the men he sent to die.
“Putin is violating international law, including the UN charter. He is violating human rights on an industrial scale and the world will not stand for it.
“There are no shades of grey to this conflict. It is about right and wrong. This is Vladimir Putin’s unprovoked war against a sovereign nation. There can be no apologising or excusing it.
“I urge nations to condemn Russia’s appalling actions and to isolate it on the international stage.”
Ms Truss will discuss the Ukrainian conflict with foreign ministers including Canada’s Melanie Joly, the Czech Republic’s Jan Lipavsky, Danish minister Jeppe Kofod and Poland’s Zbigniew Rau.
She will also hold talks with Martin Griffiths, UN undersecretary general for humanitarian affairs and emergency relief co-ordinator.
British Prime Minister Boris Johnson will also pursue diplomatic efforts on Tuesday as he is due to visit Poland and Estonia.
Downing Street said Mr Johnson was looking to use his trip to “first hand” find out “what more we can be doing and how we can be working closely together” with both countries.
He will also speak with Nato Secretary General Jens Stoltenberg while in eastern Europe.
“I will visit Poland and Estonia, two countries that are acutely affected by the current crisis in Ukraine," Mr Johnson said.
"We have shared values that are more important than ever to protect, as the humanitarian situation gets worse.
“Alongside all our international allies, the UK will continue to bring maximum pressure to bear on Putin’s regime to ensure he feels the consequences of his actions in Ukraine.
"We speak with one voice when we say, 'Putin must fail'.”
Mr Johnson also spoke to G7 and other world leaders on Monday about the situation in Ukraine.
They agreed to “pursue every avenue to ensure that Putin fails”, Downing Street said.
“The Prime Minister stressed the need for countries to continue supporting the Ukrainian government, including with the provision of defensive weapons," a Downing Street spokeswoman said.
“He also underlined the need for an international response to the emerging humanitarian crisis, including through supporting Ukraine’s neighbours to deal with large numbers of Ukrainians escaping violence in the country.
“The prime minister welcomed the unity of message and action between countries in recent days in response to Russia’s invasion.
“He stressed the need to continue applying pressure on Putin’s regime, including on Swift, with sanctions and with trade restrictions.
"The prime minister commended the progress over the weekend with all G7 countries agreeing to remove Russian banks from Swift."
Earlier on Tuesday, Ms Truss laid out plans blocking customers of all Russian banks from accessing any services in the UK.
She told Parliament that three more Russian banks would be added to the government’s sanctions list, and that new legislation will also affect Russia’s largest bank, Sberbank.
She said the move was designed to stop three million Russian companies from having access to any foreign investment from the UK.
“Global giants like Gazprom will no longer be able to issue debt or equity in London,” Ms Truss said.
“[We want] a situation where they can’t access their funds, their trade can’t flow, their ships can’t dock and their planes can’t land."
Selected banks will also be cut from the Swift international money transfer system, as politicians look to announce a total ban from Russian banks using the service.
The three named banks immediately added to the sanctions list are Russia’s national development bank, VEB; the third largest privately owned financial institution in Russia, Sovcombank; and one of Russia’s largest commercial banks, Otkritiye.
Meanwhile, Ukraine said it would launch its own "war bonds" to raise funds and analysts suggested Russia could default on its loan obligations as a result of the economic squeeze on the country.
Earlier in the day, UK Chancellor Rishi Sunak said the government would match new sanctions imposed by the US and the EU over the weekend by preventing Russian central banks from accessing cash in the UK.
The move by the UK, the US and the EU means the Russian Central Bank, National Wealth Fund and Ministry of Finance will struggle to access cash reserves.
It led to the rouble dropping more than 20 per cent against the dollar and it could have fallen further if not for the central bank raising interest rates from 9.5 per cent to 20 per cent on Monday.
Deutsche Bank strategist Jim Reid said the moves were turning the conflict into a “financial war”.
“Not only are most Russian banks now to be excluded from Swift but the Russian Central Bank’s reserves have now been effectively frozen," Mr Reid said.
“At the last recorded data in June 2021, Russia had around $630bn of foreign reserves", most of which is probably still in G10 banks and central banks.
“This is in effect a financial war now,” he said.
Central banks typically hold reserves overseas in dollars and other major global currencies.
The sanctions mean Moscow has no access to those funds, which the central banks could have used to prop up the country’s currency.
They also cannot issue new government bonds to raise fresh money because international investors are unable, or unlikely, to take on Russian debt.
“These measures demonstrate our determination to apply severe economic sanctions in response to Russia’s invasion of Ukraine," Mr Sunak said.
“We are announcing this action in rapid co-ordination with our US and European allies to move in lockstep once more with our international partners, to demonstrate our steadfast resolve in imposing the highest costs on Russia and to cut her off from the international financial system so long as this conflict persists."
The new rules also stop anyone in the UK processing any financial deals or transactions for the Russian central bank and wealth funds or various Russian banks.
It stops Russian companies from raising fresh money from international investors to refinance debt – although few are in desperate need to renew their bonds, which typically run for several years before needing to be repaid.
