MOSCOW, Sept 7 (Reuters) - Russia"s FSB security service on Tuesday accused Ukraine oforganising an attack on a gas pipeline in Russian-annexedCrimea, an allegation rejected by Kyiv which said Moscow was trying to punish prominent Crimean Tatar figures. The FSB accusedthe Ukrainian military intelligence service and the Mejlis, the outlawed representative body of the Crimean Tatars, of conspiring to blow up the pipeline on Aug. 23 outside the city of Simferopol. On Monday, a court in Crimea ordered Nariman Dzhelyalov, ex-deputy chairman of the Mejlis, to be held in custody for two months over the incident. read more Russia"s annexation of Crimea from Ukraine in March 2014 drew Western sanctions. Western countries and most of the rest of the world recognise the Black Sea peninsula as Ukrainian, and Kyiv wants the territory returned. The FSB said in a statement that the perpetrators of the blast had been promised a payment of around $2,000 by Ukraine"s military intelligence. "It has been established the sabotage was organised by a branch of the Ukrainian Defence Ministry"s Main Intelligence Directorate in the city of Kherson... with the participation of the Mejlis...," the FSB said. It said it had launched a criminal case into sabotage, an offence that can carry a prison sentence of up to 15 years. Mykola Krasnyi, a spokesperson for Ukraine"s military intelligence, denied any involvement in the pipeline incident. "POLITICAL REPRESSION" Ukraine"s foreign ministry cast the accusations and the jailing of Dzhelyalov as punishment for a summit held in Kyiv last month aimed at maintaining international attention on securing the return of Crimea to Ukraine. "The Russian Federation, as an occupying power, is obliged under international law to immediately end political repression against the local population of the Crimean peninsula," Foreign Ministry spokesperson Oleh Nikolenko told Reuters. Russia banned the Mejlis in 2016, branding it an "extremist" body. Many Crimean Tatars were opposed to the Russian annexation of the peninsula. The United States, an ally of Ukraine, has accused Moscow of targeting the Mejlis and its leadership and called for Dzhelyalov"s release.