The UK's foreign secretary announced new plans on Monday to broaden sanctions against Russian businesses and President Vladimir Putin's inner circle if an invasion of Ukraine goes ahead. The US, EU and Britain have repeatedly warned Mr Putin against attacking Ukraine after Russia posted about 100,000 troops near the border with its former Soviet neighbour. Prime Minister Boris Johnson is due to travel to Ukraine and meet President Voldoymyr Zelenskiy on Tuesday. Liz Truss said that the new proposals marked the most significant change to the UK's sanctions policy since Brexit and the toughest stance against Russia. “Whether you support Russia’s aggressive actions against Ukraine, or you’re of wider significance to the Kremlin, we will have the power to sanction you," she said. “Nothing is off the table and there will be nowhere to hide. “This will amount to the toughest sanctions regime against Russia we have had in place yet, and mark the biggest change in our approach since leaving the European Union.” London became the centre for a vast outflow of money from former Soviet republics after the 1991 collapse of the Soviet Union and opponents of Mr Putin have repeatedly called on the West to get tough on Russian money. In concert with its allies, the United States has drawn up a list of people closely linked to Mr Putin who would be hit with sanctions in the event of an attack. The US Senate is also close to finalising sanctions that could lead to Russian banks being hit and extra military aid being made available to Ukraine, for which it can pay later. Both Washington and London declined to name the people they planned to target. "The individuals we have identified are in or near the inner circles of the Kremlin and play a role in government decision making or are at a minimum complicit in the Kremlin's destabilising behaviour," a US official in Washington said. Russia is in a position to ride out the immediate impact of sanctions, with a record high of $630 billion in foreign assets held by the country's central bank in December. The current British sanctions regime only allows companies with a direct involvement in destabilising Ukraine to be targeted. Under the new plans, the programme would be widened to include Russian financial institutions, energy companies and oligarchs close to the Kremlin. Ms Truss, who is due to accompany Mr Johnson on his trip to Ukraine, said that nothing was off the table including the ability to seize property, where some of Russia's most wealthy have homes and educate their children. Kremlin spokesman Dmitry Peskov called the British warning "very disturbing". He said it made Britain less attractive to investors and would hurt British companies. "It's not often you see or hear such direct threats to attack business," he said. "An attack by a given country on Russian business implies retaliatory measures, and these measures will be formulated based on our interests if necessary." The Centre for American Progress, a US think tank, said last week that Britain would face a challenge uprooting wealthy Russians with Kremlin links from London given close ties “between Russian money and the United Kingdom’s ruling Conservative party, the press, and its real estate and financial industry". The former head of intelligence agency MI6, John Sawers, said he believed that a mixture of sanctions and military support to Ukrainian forces could stop Russia from invading. He said the practicalities of holding Ukraine would be a consideration for military planners and that could deter Russia from invading allied with the political and financial pressure. “We know that from watching the American forces in Iraq in 2003 a major, sophisticated army can march to the capital and depose a government,” he told the BBC. “The really difficult thing is to hold that territory. Ukraine is the size of Germany and France put together and 100,000 Russian troops could march to Kiev but can they hold the country?”