Russia will resume its participation in the Black Sea grain deal, the defense ministry said on Wednesday.
"The Russian Federation considers that the guarantees received at the moment appear sufficient, and resumes the implementation of the agreement," the defense ministry said in a statement.
The statement represented an about-turn by Moscow, which had previously said it would be risky and unacceptable for ships to continue sailing through the humanitarian corridor set up under a Turkish- and U.N.-brokered deal in July.
However Russian President Vladimir Putin on Wednesday threatened to leave the Ukraine grain deal again if Kyiv violated security guarantees to Moscow, hours after Russia said it was resuming its participation in the agreement.
"Russia retains the right to leave these agreements if these guarantees from Ukraine are violated," Putin said in televised comments.
But he added that even if Moscow withdraws again, it "will not interfere" in grain deliveries from Ukraine to Turkey.
Turkish Foreign Minister Mevlu Cavusoglu said on Wednesday "Russia has some security demands after the recent attack on its ships," he said of an attack on Russia's Black Sea Fleet over the weekend.
Moscow is also concerned about its fertilizer and grain exports, "which are not on the list of sanctions but the ships that are carrying these still cannot dock," Cavusoglu said, echoing comments by Russian officials.
"They still cannot get insurance and payments are not made," he said. "Therefore, a lot of countries' ships are shying away from carrying these loads."
The Russian ministry said that thanks to the involvement of the United Nations and Turkey, it had been possible to obtain written guarantees from Ukraine that it would not use the humanitarian corridor and Ukrainian ports to conduct military operations against Russia.
The Saturday suspension announcement by Moscow sent grain prices notably higher Monday on world markets.
This report was prepared using data from Reuters and Agence France-Presse