* Rasmussen says region made deep cuts as Russia re-armed
* Russia 'trying to establish new sphere of influence'
* Little enthusiasm from Czech, Slovak PMs for more spending (Adds comments on Russia/Ukraine, details)
By Jan Lopatka and Jakub Iglewski
BRATISLAVA, May 15 (Reuters) - NATO members in Central and Eastern Europe need to beef up defence spending after cutting it for the past five years while Russia has sharply increased its military budget, the head of the Western alliance said on Thursday.
NATO and its leading power, the United States, have long been urging reluctant members to spend more, but the issue has taken on new significance since Russia annexed Ukraine's Crimean peninsula in March.
"Russian defence spending has grown by more than 10 percent in real terms each year over the past five years," NATO Secretary General Anders Fogh Rasmussen told a security conference in Slovakia, one of four alliance members - with Poland, Hungary and Romania - that share a border with Ukraine.
"By contrast, several European NATO countries have cut their defence spending by more than 20 percent over the same period.
"And the cuts have been particularly deep here in central and eastern Europe. This is unsustainable. Now is the time to stop the cuts and start reversing the trend."
Rasmussen said Russia had not met the commitments it made at a meeting in Geneva last month to help defuse the crisis in Ukraine, where pro-Russian separatist militants have taken over parts of the south and east.
"Judging by Russia's actions, the aim is clear. Russia is trying to establish a new sphere of influence in defiance of international law and fundamental agreements that Russia itself has signed," he said.
"This has profound long-term implications for our security and it requires serious long-term solutions."
Russia says the pro-Western Ukrainian government should be using dialogue, not military force, to resolve the crisis, and assets the right to intervene in its neighbour if necessary to protect the rights of Russian-speakers.
The flare-up of Cold War-style tensions has alarmed countries in Central and Eastern Europe that only emerged from decades of domination by Moscow when they threw off Communism in 1989.
But speeches by regional prime ministers at the same Bratislava conference made clear that Rasmussen has his work cut out to persuade them to find more cash.
"Let me put it very frankly: In Slovakia, I cannot imagine in the following years any scope to increase defence spending," Slovak Prime Minister Robert Fico said earlier.
Czech Prime Minister Bohuslav Sobotka said his government would look to stop a spending decline in its 2015 budget but saw no significant increases.
The Slovaks and Czechs each spent around 1 percent of gross domestic product on defence last year, down about half a percentage point since 2009, according to NATO statistics.
Poland was the closest to the goal of 2 percent that NATO sets as a target for its members. It spent 1.8 percent of GDP, and has expressed a willingness to increase that.
Poland's Prime Minister Donald Tusk told the conference NATO needed to have a larger presence in eastern Europe in light of the crisis in Ukraine.
NATO is already bolstering the security of eastern members with more ships, troops and troops. Its top military commander said earlier this month that the alliance would have to consider permanently stationing troops in parts of eastern Europe. (Writing by Jason Hovet; Editing by Mark Trevelyan)
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