UNITED NATIONS, United States (AFP) - An emergency UN Security Council meeting on Ukraine began Monday, called by Russia to set out in greater detail its policy after being threatened by US and EU sanctions.

"I'll be explaining in considerably more detail the position of the Russian Federation in the current situation in Ukraine and what is making Russian policy," ambassador Vitaly Churkin told reporters before the emergency session got underway.

It is the council's third emergency meeting in four days on Ukraine, where the government says Russian troops are still pouring into Crimea, in violation of international accords.

Saturday, a meeting of the envoys from the council's 15 member states ended in disagreement between the West and Russia, with Washington and London urging Moscow to pull back its military reinforcements from the strategic Black Sea peninsula with a majority ethnic Russian population.

Saturday's open meeting began with a two-hour standoff over procedure as Moscow fought the presence of cameras and of Ukraine.

According to a diplomat on the council, Russia "was taken aback Saturday and wants to give its read on events, especially as things go south on the ground."