Ukraine crisis: Nato warns Russia against further intervention

Nato has warned Russia that further intervention in Ukraine would be a "historic mistake" with grave consequences. 

Secretary-General Anders Fogh Rasmussen said Moscow must pull back troops it has massed on the Ukrainian border.

Ukraine has regained control of one of the government buildings occupied by pro-Russian activists in the east of the country, in the city of Kharkiv.

However, armed militants are refusing to withdraw in another city, Luhansk.

Read more: BBC News - Ukraine crisis: Nato warns Russia against further intervention