Boris Johnson has compared Vladimir Putin to a drug dealer who managed to hook western nations on Russian supplies of oil and gas, ahead of a trip to the Middle East in an attempt to diversify the sources of Britain’s energy imports. The UK prime minister urged European countries to “get ourselves off that addiction” and said he wanted support from “the widest possible coalition” to help offset the pressures caused by spiralling oil and gas prices. As he prepared to set off for talks with the leaders of Saudi Arabia and the United Arab Emirates, Johnson was questioned about the murder of the journalist Jamal Khashoggi. US intelligence agencies found last year that the Saudi crown prince, Mohammed bin Salman, approved the killing – though he has denied this. Johnson said: “I think that we’ve got a global crisis in which it’s obvious that the Russian aggression in Ukraine has helped to trigger a spike in the price of hydrocarbons, a spike in the price of oil. “It’s vital – if we are going to stand up to Putin’s bullying, if we are going to avoid being blackmailed by Putin in the way that so many western countries sadly have been – we have got to get ourselves off Russian hydrocarbons.” He added that the brutality of Russian forces in Ukraine was “quite unbelievable” and the indiscriminate targeting of civilians and bombing of cities was last seen “in the European continent 80 years ago”. Johnson is likely to confront Prince Mohammed over the recent execution of 81 men in 24 hours. However, Downing Street has refused to say if he would also bring up the murder of Khashoggi. As well as pressing Saudi Arabia to raise its production of oil and gas to make up for a reduced supply from Russia, the prime minister is expected to discuss the development of renewable energy supplies, and security issues in the Middle East. Johnson’s visit came as the UK imposed sanctions on 370 more Russian individuals, including more than 50 oligarchs and their families with a combined net worth of £100bn. The move was expected, given the passing in parliament overnight of the economic crime bill, which the government said would help it replicate sanctions imposed by the EU. Meanwhile, 89,000 Britons have so far put themselves forward to sponsor Ukrainian refugees, after the government was criticised for moving too slowly to help the hundreds of thousands of people who have fled Ukraine. In an article for the Daily Telegraph, Johnson admitted western countries had made a “terrible mistake” by letting Putin “get away” with annexing Crimea in 2014 and allowing themselves to become more dependent on Russian power sources. However, he warned Britons that divesting from Russian power would be “painful” and that the financial assistance offered by the chancellor, Rishi Sunak, to help with rising bills this year could not be afforded for long. Last week, the UK government announced a plan to phase out imports of Russian oil by the end of the year. Before his flight to Riyadh, Johnson hosted leaders from the Joint Expeditionary Force, an alliance of northern European countries. Representatives from Denmark, Finland, Estonia, Iceland, Latvia, Lithuania, the Netherlands, Sweden and Norway had been expected to dine with Johnson at his Chequers country retreat on Monday night before talks in London on Tuesday.