Nato has urged Russia to withdraw its troops and armour from Ukraine and accused it of "massive militarisation" around the fringes of Europe, as the alliance traded barbs with Moscow ahead of a major summit next month.
After Nato defence ministers approved the deployment of more troops to the three Baltic states and Poland to allay fears of Russian aggression, its secretary general said Moscow was still fuelling a separatist uprising in eastern Ukraine.
Russia continues to deny giving military help to the separatists and, having denounced Nato’s Baltic plans as an aggressive provocation, it warned the alliance against bolstering its forces in the Black Sea – close to the Crimean peninsula that the Kremlin annexed from Ukraine in 2014.
"Russia needs to stop supporting the militants and withdraw its forces and military equipment from Ukrainian territory," Nato secretary general Jens Stoltenberg said after the alliance's defence ministers met their Ukrainian counterpart in Brussels.
He said a ceasefire agreed in February 2015 was being “violated again and again, and this is of great concern”, as international monitors reported intensified shelling in eastern Ukraine and the return of many heavy weapons to the front line.
Ukraine's defence minister, Stepan Poltorak, said 623 of the country's servicemen had been killed in the east this year, in a conflict that has claimed almost 10,000 lives, injured 20,000 people and displaced more than two million.
There has been little progress in implementing the so-called Minsk agreements on halting fighting in the east, giving broad autonomy to the region, holding local elections there and re-establishing Ukraine's control over its side of long stretches of the border with Russia.
In Poland this month, Nato launched its biggest exercises since the Cold War, and confirmed plans to deploy international battalions to the Baltic states and Poland, in a move that will be confirmed at a summit in Warsaw on July 8th-9th.
Mr Stoltenberg said Nato leaders would also use the summit to “take decisions on a tailored presence for the southeast region, with a land element built around a multinational framework brigade in Romania”.
Moscow bristled when the United States activated part of a missile defence system in Romania last month, and it warned Nato this week not to boost forces in the Black Sea area, where Russia maintained a major base in Crimea even before it seized control of the peninsula.
"If a decision is made to create a permanent force, of course it would be destabilising, because this is not a Nato sea," said Andrei Kelin, a senior official at Russia's foreign ministry.
Russia has also held a series of major war games and bolstered its presence in strategic maritime areas, including Crimea and the Syrian coast.
"We are observing massive militarisation at Nato borders: in the Arctic, in the Baltic, from the Black Sea to the Mediterranean Sea . . . Russia is trying to build up a zone of influence through military means," Mr Stoltenberg told German newspaper Bild on Thursday.
“We are registering aggressive, unannounced, large-scale manoeuvres on the Russian side. Therefore we must act.”