THE UN warned on Thursday of a new threat to global food security due to Russia limiting the number of ships allowed to pick up Ukrainian grain at Black Sea ports.

UN spokesman Stephane Dujarric expressed serious concern that only 33 ships departed from Ukrainian ports in May, half the number compared to April, and exports of grain and other foodstuffs totalled just 1.3 million metric tonnes last month, less than half the amount for April.

He said Russia informed the centre in Istanbul co-ordinating the arrivals, departures and inspections of ships involved in the Black Sea Grain Initiative “of its decision to limit registrations in the port of Yuzhny as long as ammonia is not exported, and currently it’s not.”

Ammonia is a key ingredient for fertiliser and Moscow wants Ukraine to open a pipeline from the Russian city of Togliatti to the Ukrainian port of Odessa that it used before the war to ship ammonia to its global customers.

Turkey and the UN brokered the breakthrough initiative with Russia and Ukraine last July, opening a path for Ukrainian grain exports from three of its key Black Sea ports — Odessa, Chernomorsk and Yuzhny.

In a separate memorandum, the UN said it would work to overcome obstacles to Russian food and fertiliser shipments.

Meanwhile, the US announced on Thursday that it will revoke the visas of Russian nuclear inspectors, denying pending applications for new monitors and cancelling standard clearances for Russian air craft to enter US airspace.

The State Department said it was taking the steps and others in response to Russia’s “ongoing violations” of New Start, the last arms control treaty remaining between the two countries.

The US will, however, continue to notify Russia when it conducts test launches, it said, adding that the steps it was taking were reversible provided Moscow returns to compliance with the treaty.

Elsewhere, China’s envoy to Ukraine appealed to other governments today to “stop sending weapons to the battlefield” and hold peace talks.

“China believes that if we really want to put an end to war, to save lives and realise peace, it is important for us to stop sending weapons to the battlefield, or else the tensions will only spiral up,” Mr Li told reporters.