UNITED NATIONS, May 25 (Reuters) - Russia signaled on Thursday that if demands to improve its grain and fertilizer exports are not met then it will not extend beyond July 17 a deal allowing the safe wartime export of the same products from three Ukrainian Black Sea ports.

It made the same threat and demands in March. Moscow then agreed last week to renew for 60 days the Black Sea export pact - initially brokered by the United Nations and Turkey last July with Russia and Ukraine to try to ease a global good crisis aggravated by Moscow's February 2022 invasion of Ukraine.

Since March Russia appears to have prioritized two specific demands: restarting a pipeline to transport Russian ammonia to the Ukrainian Black Sea port of Pivdennyi for export to global markets; and reconnecting Russia's agricultural bank, known as Rosselkhozbank, to the SWIFT international payment network.

"If Rosselkhozbank is not connected to SWIFT and there is no progress on the implementation of other 'systemic' problems that are blocking our agricultural exports, then the 'Black Sea initiative' will also have to look for alternatives," Russia's Foreign Ministry said in a statement on Thursday.

It suggested land exports through Europe as an alternative, saying that avenue was more costly for Ukraine.

Rosselkhozbank was cut off from SWIFT by the European Union in June over Russia's invasion. An EU spokesperson has said the bloc is not considering the reinstatement of Russian banks.