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MOSCOW, April 11 (Reuters) - Russian Foreign Minister Sergei Lavrov called on Friday for legal guarantees of Ukraine's neutrality, underlining Moscow's determination to keep the neighbouring former Soviet republic out of NATO.
Lavrov said Moscow was ready for four-party talks next week with the United States, the European Union and representatives of Ukraine and suggested Ukraine's gas debt to Moscow should be on the agenda, Russia news agencies reported.
But he suggested Moscow would try to use such talks to shape Ukraine's future and keep it from moving too close to Europe and the United States under the pro-Western leadership in power following the ouster of President Viktor Yanukovich.
"Firm guarantees of the preservation of Ukraine's non-aligned status law, are needed," Lavrov said at a meeting with Russian non-governmental organisations, adding that the guarantees should be "enshrined in law".
"Ukraine should not be a bone of contention, but a link in the chain of security architecture," Lavrov said. Yanukovich signed legislation in 2010 barring Ukraine from joining any military alliance.
NATO is concerned over what it says is a Russian military buildup near Ukraine's border following Moscow's annexation of its Crimea region last month, which turned tension over turmoil in Ukraine into the biggest East-West crisis since the Cold War.
Lavrov said that to resolve the crisis, the West should "halt attempts to legitimise the government of the Maidan" - a reference to the Kiev square at the centre of protests that pushed Yanukovich from power.
He reiterated Russia's demand that Ukraine adopt constitutional reforms with strong input from all its regions.
Russia says the rights and interest of its compatriots in eastern and southern Ukraine are being ignored, and President Putin has reserved the right to send in the armed forces to protect them.
(Reporting by Gabriela Baczynska, Writing by Steve Gutterman, Editing by Timothy Heritage)