Prime Minister Boris Johnson has said the West made a "terrible mistake" and let President Vladimir Putin "get away" with annexing Crimea in 2014.
TurkicWorld reports that, writing in the Telegraph, Mr Johnson said ending the West's dependence on Russian oil and gas was vital to "end the bullying" from the Kremlin.
It comes as the foreign secretary is expected to announce further sanctions.
In his article in the Telegraph, Mr Johnson said: "When Putin invaded Ukraine the first time round, in 2014, the West made a terrible mistake. The Russian leader had committed an act of violent aggression and taken a huge chunk out of a sovereign country - and we let him get away with it."
Crimea, in the south, was annexed by Russia from Ukraine in 2014 and is home to a sizeable Russian military presence.
Mr Johnson said the only way to halt President Putin's "continuous blackmail" was by ending Western countries' dependence on Russian oil and gas - a process that would be "painful".
He also said his promised Energy Security Strategy for the UK would "double down" on wind energy, exploit solar power and make a "series of big new bets" on nuclear energy. Further drilling in the North Sea was one suggestion he made.
The UK is to phase out Russian oil imports by the end of 2022.
