Britain has compiled a “hit list” of Russian oligarchs who will face sanctions over the coming weeks, the foreign secretary, Liz Truss, has said. She said there were more than 100 billionaires in Russia and that some of them would face “a rolling programme of sanctions” as officials compiled the evidence to justify their assets being frozen in the UK. “We are targeting oligarchs’ private jets, we’ll be targeting their properties, we’ll be targeting other possessions that they have,” she told Sky’s Trevor Phillips on Sunday. “There will be nowhere to hide.” Truss also said the government would be bringing forward its long-awaited economic crime bill this week to make it easier for assets to be targeted, by enforcing more transparency about ownership. The government has been criticised because so far only eight Russian oligarchs have been identified as being subject to individual UK sanctions. The Russian president, Vladimir Putin, and foreign minister, Sergei Lavrov, have also been sanctioned by the UK, but that announcement was seen as symbolic because neither Putin nor Lavrov are thought to have assets in Britain. Truss has said that drawing up the paperwork to justify individual sanctions is not straightforward because individuals at risk of being singled out have already contacted the Foreign Office threatening legal action against any sanctions decision. Asked on Sky if Roman Abramovich, the owner of Chelsea football club, was on her hit list, Truss refused to say. But she insisted that the government was determined to respond toughly to the Russian invasion of Ukraine because it believed it had not done enough in the past to confront Putin. “Frankly, over the past 15 year we haven’t done enough to stand up to Putin,” she said. “We’re now facing the reality of what that means. And that is why we are taking a much tougher stand now.” In particular, she said Britain and the west did not do enough to deter Putin in 2008, when he invaded Georgia, and in 2014, when he seized Crimea, which was part of Ukraine. In her Sky interview Truss also warned that the current conflict in Ukraine could last for “a number of years”. She said she thought it could lead eventually to the downfall of his regime, but that before then Putin could resort to using more brutal tactics and weaponry in the conflict. Without giving details, she said: “I fear this conflict could be very, very bloody.” She said: “This could well be the beginning of the end for Putin. And I fear that he is determined to use the most unsavoury means in this war.” Truss also signalled that the government was likely to ease the current restrictions on Ukrainians seeking refuge in the UK, saying an announcement about changes to visa rules was coming “very shortly”. Individuals who are subject to sanctions usually face travel bans and having their assets in the UK frozen, although the exact terms of sanctions instruments can vary. David Lammy, the shadow foreign secretary, told the same programme that the UK sanctions had not gone far enough. He asked why there were individuals who had been sanctioned by the US but not the UK, and said: “We can’t understand why it’s still the case that there are major Russian banks that are not subject to sanctions.”