Former foreign secretary Sir Malcolm Rifkind has called for tougher sanctions to ensure Russia changes policy in eastern Ukraine, describing previous measures against Vladimir Putin "pretty useless".
"When you get into the situation of preventing them having access to financial markets, preventing high quality technology exports to their energy industry, that goes to the very heart of the Russian economy," he told BBC Radio 4's Today programme.
Sir Malcolm said world leaders must make clear to Mr Putin that he needs to leave the Ukrainians to "resolve their own problem", by ceasing to provide military equipment and other support to separatist rebels.
However, he described Nick Clegg's call for Russia to lose hosting rights to the 2018 World Cup as "pretty amateur", adding: "A heck of a lot is going to happen between now and then."
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