Oil prices are climbing on fears that the Ukraine-Russia crisis will disrupt supplies across the world.

The price of Brent crude, an international benchmark, reached a seven-year high of $97.76 (£72) a barrel on Tuesday.

Russia ordered troops into two rebel-held regions in Ukraine’s east after it recognised them as independent states.

Asian stock markets closed lower, and US and European stock exchanges were braced for losses.

The UK  and several western allies have threatened sanctions on Russia, which is the second largest oil exporter after Saudi Arabia. Russia is also the world’s top producer of natural gas.

Russia has said its troops will engage in “peacekeeping” in the self-declared Donetsk and Luhansk people’s republics.

But the US has said calling them peacekeepers is “nonsense”, and that Russia is creating a pretext for war.

The Ukraine-Russia crisis could have “substantial implications” on oil prices, said Sue Trinh of Manulife Investment Management.

Sanctions forcing Russia to supply less crude or natural gas would have “important impact on the global economy,” she added.