* Rally was planned to mark anniversary of mass deportation
* Russian President Putin meets Tatars in Sochi
* Interests of Tatars today tied to Russia, says Putin (Adds Crimean Tatar leader's quotes, background)
By Denis Dyomkin and Alexander Winning
SOCHI, Russia/SIMFEROPOL, Crimea, May 16 (Reuters) - A Crimean Tatar leader condemned as "inhuman" an official ban on commemorations of Stalin's persecution of Tatars - hours after Russian President Vladimir Putin promised to help the ethnic group.
Crimean Prime Minister Sergei Aksyonov issued a decree on Friday banning all mass gatherings in the region, annexed by Russia in March from Ukraine, until June 6. He cited violence in southeast Ukraine as the reason.
The Mejlis, the Crimean Tatars' main representative body, had planned to hold a rally in regional capital Simferopol on May 18, the date Soviet deportations of Tatar families began in 1944. Many of the 200,000 deportees died on their way into exile.
Refat Chubarov, chairman of the Mejlis, described the decree as an "inhuman act" at a news conference on Friday.
"What do the authorities want to show the Crimean Tatars on their day of national mourning, on a day when they say prayers for the souls of their deceased?" he said.
Chubarov said the Mejlis would take a final decision on how to respond to the ban on Saturday but warned many Tatars were likely to take to the streets in protest.
Putin met representatives of the Crimean Tatars in Sochi, southern Russia, on Friday and said Russia would improve their lives - but added that they must accept their future lay with Russia after Moscow's takeover of their Black Sea homeland.
The Muslim, Turkic-origin Tatars make up more than 12 percent of Crimea's population of 2 million. Many still associate Moscow's rule with oppression, exile and suffering.
Their situation was described by the 57-nation OSCE rights and democracy forum this week as "particularly precarious" since the annexation.
TATARS "TIED TO RUSSIA"
Putin said on Friday a decree he signed last month to "rehabilitate" the Tatars - accused by Stalin of sympathising with Nazi Germany - was part of an effort "to establish a normal livelihood and create conditions for the strong development of the Crimean Tatar people in their homeland".
The meeting at Putin's residence in the Black Sea resort of Sochi reflected a split in sentiments among Crimean Tatars. It included Vasvi Abduraimov, a leader to whom Putin recently awarded a state medal for backing the annexation.
Many Tatars wanted Crimea to remain in Ukraine and boycotted the March 16 referendum in the region, in which authorities said nearly 97 percent of voters backed joining Russia.
"We are ready to work with all people ... but none of us can allow the Crimean Tatar people to become a bargaining chip in disputes ... especially in disputes between Russia and Ukraine," Putin said.
He appeared to single out Mustafa Dzhemilev, 70, a Soviet-era dissident and former head of the Crimean Tatar assembly, who is a member of Ukraine's parliament and has denounced the referendum.
"I understand that there are people who ... have done a lot for the Crimean Tatars and who fought for their rights for decades," Putin said. "But today we must all realise that the interests of the Crimean Tatars today are tied to Russia.
"One must not defend the interests of Crimean Tatars who live in Russia, in Crimea, from within the parliaments of other countries. This is just nonsense, it's a joke."
The Crimean Tatar Mejlis last month accused Russia of barring Dzhemilev from Crimea.
Russia's annexation of Crimea, shortly after mass protests toppled Ukraine's pro-Moscow president, turned an already tense dispute into the worst crisis in relations between Moscow and the West since the Cold War.
In a report that was issued on Friday and immediately criticised by Russia, U.N. monitors said serious human rights problems were emerging in Crimea and expressed concern about the treatment of religious and ethnic minorities, among others. (Writing by Steve Gutterman and Alexander Winning; Editing by Andrew Roche)