Russia has said the number of Ukrainian military forces deployed in the southeast of the country should cause "deep concern" among members of the Organization for Security and Cooperation in Europe.
In a statement, the Russian Foreign Ministry said there were more than 11,000 Ukrainian troops, 160 tanks, 230 armoured vehicles and 150 artillery pieces deployed in the region as part of an operation to counter pro-Russian separatists.
More top news
Experts have warned that Ash dieback's impact on millions of trees could have serious consequences for the landscape and wildlife.
White House officials said that the US intelligence community has confirmed the death of Afghan Taliban leader Mullah Omar.
Jamie Oliver and health experts have been asked to help the Government in tackling the problem of obesity in primary school children.