The mansions and private jets of billionaires are to be targeted as the government steps up punitive measures following Russia's aggression against Ukraine.

Speaking to the Trevor Phillips On Sunday show, Ms Truss also confirmed that ministers would bring new legislation to the House of Commons in the coming days in order to crack down on dirty money flowing into the UK.

However, she also warned that there would be an "economic cost" to the UK as the West sought to cut the Russian economy "at its knees" and hobble the military might of Mr Putin, the Russian president.

On Saturday night, the UK, US, Canada and EU vowed to block some Russian banks from using the SWIFT financial messaging system, impose measures on the Russian Central Bank to prevent it undermining the impact of Western sanctions, and take further action against individuals and companies linked to the Kremlin.

"The real objective is to degrade the Russian economy because what we know is that Putin's war machine is funded by revenues from oil and gas," Ms Truss said.

"So what we have to do is reduce dependency on oil and gas.

"We have to cut the ability of Russia to raise money on the international financial markets, we are cutting the technology that they can use in their military complex - they have got very advanced weapons and we are going to stop them accessing Western technology."

The foreign secretary added that the aim of sanctions was to make it "harder and harder" for Mr Putin to wage war, but admitted it would "take time" as she suggested there would be a "long-running conflict" in Ukraine.

Highlighting some of the further action that would be taken by the UK government against Russians and Russian interests, Ms Truss said: "There are over 100 billionaires in Russia, we have compiled a hit list of oligarchs, we're working through putting the cases together and every few weeks we will sanctions new oligarchs.

"There will be a rolling programme of sanctions, we will go through the hit list.

"We are targeting oligarchs' private jets, we'll be targeting their properties, we'll be targeting other possessions that they have and there will be nowhere to hide."

However, the foreign secretary did not say whether or not Chelsea football club owner Roman Abramovich - who has transferred his "stewardship and care" of the club to a charitable foundation - was on the "hit list".

Ms Truss also confirmed that the government's Economic Crime Bill - which is expected to include measures to crack down on abuse of shell companies and to unmask the real owners of offshore companies that own UK property - would be introduced to parliament this week in order to "create a lot more transparency around the structures of these companies and make it much clearer what is going on".

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Following Russia's fresh aggression against Ukraine, the foreign secretary welcomed a "huge change" in Western attitudes to Mr Putin's regime as she admitted that G7 countries "didn't do enough" to deter the Russian president after his military action against Georgia in 2008 and annexation of Crimea in 2014.

"We simply cannot afford to be importing Russian oil and gas, we cannot afford to have such a strong Russian presence in our financial system," she said.

"That is why we are prepared to take tough actions; it will also be difficult for our economy in the short-term but it will help to preserve freedom and democracy in the long-term."

The foreign secretary acknowledged there would be "economic cost here in Britain" - in terms of access to oil and gas markets - as a result of Western action being taken against Russia.

But she said these would be "nothing like" the sacrifices of Ukrainians, and added: "I firmly believe that the British public understand the price we will pay if we don't stand up to Putin now."

Ms Truss said she would support the idea of having ceilings on how much oil and gas is imported from Russia so over time we cut the dependency right across Europe".

Labour's shadow foreign secretary David Lammy called for more Russian banks and the family members of oligarchs to be included among UK sanctions.

"There should be more banks listed," he told Sky News.

"We can't understand why it's still the case that there are major Russian banks that are not subject to sanctions."

He also repeated his party's call for the UK's action against Russia to include the expulsion of the country's ambassador.

Brian O'Toole, a former US Treasury official, suggested if Ukrainians could resist Russia's invasion for long enough, then Western sanctions "may prevent Russia from re-arming itself".

"Putin will lack the money, he will lack the supplies and he will lack - to a certain extent - the morale within his troops that seems to be on the edge at the moment," he told Sky News.