Russia says there will be no extension of the U.N.-brokered Black Sea grain deal beyond May 18th, unless the West removes a series of obstacles to the export of Russian grain and fertilizer.

The Ukraine grain Black Sea export deal was brokered by the United Nations and Turkey last July, to help alleviate a global food crisis worsened by conflict disrupting exports from two of the world’s leading grain suppliers.

To help persuade Russia to allow Ukraine to resume its Black Sea grain exports last year, a separate three-year agreement was also struck in July, in which the United Nations agreed to help Russia with its food and fertilizer exports.

Russia says the two agreements were “interconnected parts of one ‘package’” and scolded the U.N. Secretariat for what it said was a distortion of the facts.