The North Atlantic Treaty Organisation (Nato) is today expected to establish a 10,000-strong Rapid Reaction Force that could be deployed within days, in the latest sign of worsening relations with Russia.
The European Union and the United States are to stiffen sanctions against Russian companies, though only a subsidiary of the largest State-controlled energy company, Gazprom will be affected.
The military force, led by Britain, comes as Eastern European states warned that Nato and the EU have failed to stand up to Russian president, Vladimir Putin.
Urging agreement, British prime minister David Cameron said Nato had stood down its "high-readiness force" in 2002, but there is now an urgent need for a new one.
It must be capable of being deployed within two to five days “anywhere in the world”, he said, adding that Britain will contribute 3,500 soldiers, plus equipment.
He said Nato countries must spend 2 per cent of GDP on defence, with a fifth of that going on new equipment: “That would send a strong message to those who threaten us.”
Lithuania's president Dalia Grybauskaite declared: "Russia is at war against Ukraine and that is a country which wants to be part of Europe. Russia is practically at war against Europe."
The Lithuanians have already agreed to take part in the Rapid Reaction Force which is due to be announced this afternoon at the end of the Nato summit in South Wales.
The Danes, Estonia, Latvia, the Dutch and the Norwegians have also agreed to take part in the force, which could be deployed outside of Nato’s borders in exceptional circumstances.
Today, there are hopes in Minsk that a ceasefire could be called in the Ukraine conflict, but most Nato leaders are suspicious of Putin’s intentions.
Last night, the Nato Secretary-General Anders Fogh Rasmussen said Mr Putin had done nothing at any point to stop conflict, and everything he could to encourage it.
His declaration came after Nato leaders offered help short of weaponry to the Ukrainian president, Petro Poroshenko, who spoke last night to journalists.
“Ukraine is fighting for peace, we did not instigate war. Ukrainians are the ones who are paying the highest price with the loss of life of soldiers and innocent civilians,” he went on. He said he would order a ceasefire later today of his forces if an agreement can be reached in the Minsk talks: “I want to do my best to stop the war.
Meanwhile, Nato leaders will again discuss the threat posed by Islamic State (formerly known as ISIS) in Iraq and Syria, though it is clear that London is concerned by the lack of pace in Washington's response to the threat.
The US has said it will form a “core coalition” to battle Islamic State militants in Iraq, calling for broad support from allies and partners but ruling out committing ground forces.
“We need to attack them in ways that prevent them from taking over territory, to bolster the Iraqi security forces and others in the region who are prepared to take them on, without committing troops of our own,” US Secretary of State John Kerry told a meeting of 10 nations.
No plans have yet been put forward by the US about possible British involvement in air-strikes, British sources said, while a formal request for help is some way off.
Mr Cameron has emphasised that a formal request for assistance from a new, representative Iraqi government could be in place by September 11th, if there are no more delays.
Additional reporting from Agencies
