Kiev said the maneouvres would be conducted under the 1994 Budapest Memorandum, a document signed by Britain, American and Russia to guarantee Ukraine’s territorial integrity after it gave up its share of Soviet nuclear bombs.
However, a Downing Street source said Britain had not “committed” itself yet to the exercises and declined to elaborate on whether they would involve sending British forces to the Black Sea region.
The calls for a show of Western strength come as Europe appeared to be at odds over how to respond forcefully to President Vladimir Putin’s military annexation of Crimea.
While maintaining a united stance in public, the individual responses of Britain, France and Germany are all conditioned by the degree to which their economies are vulnerable to Kremlin retaliatory measures.
Britain is keen to minimise damage to the City of London, Germany frets about Russia cutting off gas supplies and France has valuable Kremlin defence contracts.
The differences were exposed on Wednesday when David Cameron, with French support, said that world leaders should consider excluding Russia permanently from G8 meetings when they convene for a nuclear security summit in The Hague on Monday.
“I think we should be discussing whether or not to expel Russia permanently from the G8 if further steps are taken,” he told Parliament.
“I think that’s the right way to proceed.”
Angela Merkel, the German chancellor, with Italian support, has backed the suspension of a showcase G8 summit hosted by Mr Putin in Russia this June.
But she is resisting moves to expel the Russians outright on the basis that it would close the door to an important diplomatic forum.
Signs of the splits in Europe emerged as Russia moved decisively to evict Ukrainian forces from the annexed Crimean peninsula.
Pro-Russian militias backed by Russian soldiers overran at least two Ukrainian military bases on Wednesday, and arrested the commander of the Ukrainian navy in Crimea, Rear Adml Sergei Haiduk.
Rather than face a fight in which they were outnumbered, the Ukrainian troops packed up their uniforms and belongings and quit their bases, seemingly for good.
Despite the brazen nature of the Crimea’s military annexation, Mrs Merkel does not agree with Mr Cameron that it should be the trigger for a fresh round of tougher EU sanctions.
She insists that only Russian military incursion into east Ukraine, beyond Crimea, counts as escalation.
The different approaches mean that next week’s two-day meeting of EU leaders will be divided over when to begin an arms embargo or energy and financial sanctions to “change Russian behaviour”.
A senior European diplomat said:
“We need to take action that really changes Russian calculations and we need a sober view as to what Russian reactions will be to further measures.
“We will face over the coming days and weeks, Russian retaliatory action and an attempt to divide and expose the vulnerabilities of the EU.
“The EU needs to demonstrate that it is serious and that it is united. There are people, in terms of energy disruption, who are more vulnerable than others to specific Russian threats.”
Germany and Italy are heavily economically dependent on Russian gas and oil imports, while countries such as Britain are not.
Britain has introduced an arms embargo on Russia, but France has held back because it has a £1 billion ($1.65 billion) contract to supply two warships to Russia.
France has urged Britain to support financial sanctions that would hit the City of London, demands that also rattle German and Italian companies.
Diplomats are working on a sanctions list that could take weeks or months to ensure the impact is “equitably shared” across the EU.
“There will be pain and consequences inside the EU for all our economies and societies,” said one.
Meanwhile, the pro-Western government in Ukraine angered Moscow further on Wednesday by announcing that it would withdraw from the Moscow-led Commonwealth of Independent States alliance, which replaced the Soviet Union.
The move means all Russians coming to Ukraine need visas.
Critics said it risked backfiring, not just by jeopardising trade relations, but by giving Russia an excuse for a reciprocal visa requirement for Ukrainians visiting Moscow.
Andriy Paruby, the secretary of the security council in the new Kiev government, also called for all Ukrainian forces to withdraw from Crimea, for the United Nations to recognise Crimea as a demilitarised zone.
Source: The Telegraph