Moscow on Thursday urged the United Nations, which sponsored a deal to free Ukraine's grain shipments from a Russian blockade of its Black Sea ports, to help fulfil the parts of the deal intended to ease Russia's food and fertiliser exports.
Russia on Wednesday resumed participating in the initiative after a four-day suspension, relieving pressure on food prices and easing fears of a renewed global food crisis.
The arrangement is due to expire on Nov. 19, and Moscow has made clear it wants more done to ensure it can export its own huge food and fertiliser output despite the barrage of Western sanctions imposed in response to its invasion of Ukraine.
"We still do not see any results regarding a second aspect: the removal of obstacles to the export of Russian fertilisers and grain," Foreign Minister Sergei Lavrov told a news conference in Amman, Jordan.
"We have once again called on the United Nations Secretary General to ensure that he fulfils the obligations he agreed to through his own initiative," Lavrov added. He said the situation needed to be resolved "in the very near future".
"If we're talking about the volumes of fertilisers and grain in question, then these volumes from the Russian side are incomparably higher than from the Ukrainian side."
Russian agricultural exports do not fall explicitly under sanctions imposed by the United States, European Union and others, but Moscow says they are badly hindered by the restrictions imposed on its financial, logistics and insurance sectors.
The initiative - brokered by Turkey and the United Nations - was agreed in July for 120 days.
Asked on Thursday whether Russia's decision to return to the deal meant it was ready to agree to an extension, Kremlin spokesman Dmitry Peskov said: "No, it does not mean that."
"It is necessary to assess ... how all aspects of the deal are being implemented, all the parameters of the agreements, and then come to a decision."
Russia had suspended its participation over an attack on its Crimean naval port of Sevastopol, but returned to the deal on Wednesday having secured little in return and promising that, even if it withdrew again, it would not impede shipments from Ukraine to Turkey.
(Reporting by Reuters; editing by Guy Faulconbridge and Kevin Liffey)