Russian officials are in Belgrade to discuss a key energy deal with Serbia.

The talks follow the Serbian parliament's ratification earlier this months of a gas and oil agreement between the two countries.

The deal envisages that part of a pan-European gas pipeline will run through Serbia and that Russia will buy Serbia's state oil monopoly, NIS.

Serbia and Russia signed the agreement in January but many details still must be resolved, including how much gas will run through Serbia.

The Russian delegation is headed by the Emergency Minister Sergei Shoigu, who meets Monday with Serbia's Prime Minister Mirko Cvetkovic and other senior officials.