The European Union and the United States have brought fresh sanctions against Russia via its oil companies.
Western leaders want to force President Vladimir Putin into using his influence in eastern Ukraine where fighting still rages.
Pressure has upped since the crash of Malaysian flight MH17 over Ukraine, killing 298 people, with pro-Russian separatists suspected of shooting it down.
Yesterday US President Obama said: “The United States is imposing new sanctions in key sectors of the Russian economy: energy, arms and finance. We’re blocking the exports of specific goods and technologies to the Russian energy sector.”
He expressed disappointment that Russia and its “proxies” in Ukraine “have failed to cooperate with the investigation and to take the opportunity to pursue a diplomatic solution to the conflict in Ukraine”.
European Commission President Manuel Barroso and President of the European Council Van Rompuy said in a statement this includes curtailing “Russian access to sensitive technologies particularly in the field of the oil sector”.
Prime Minister David Cameron met with families of some MH17 victims yesterday and he told BBC North West: “It’s a deeply awful, harrowing and dreadful incident that’s taken place.”