Russia announced it will cut gas supplies to Europe from Wednesday in a blow to countries that have backed Ukraine and provided military equipment.
While missile attacks in Black Sea coastal regions raised doubts about whether Russia will stick to a deal to let Ukraine export grain.
The first ships from Ukraine may set sail in days under a deal agreed on Friday, the United Nations said, despite a Russian missile attack on the Ukrainian port of Odesa over the weekend, and a spokesman for the military administration in the saying another missile had hit the Odesa region on Tuesday morning.
Soaring energy costs and the threat of hunger faced by millions in poorer nations show how the biggest conflict in Europe since World War Two, now in its sixth month, is having an impact far beyond Ukraine.
The EU countries are set to approve on Tuesday a weakened emergency proposal to curb their gas demand as they try to wean themselves off Russian energy and prepare for a possible total cut-off.
On Monday, Russian energy giant Gazprom, said gas flows to Germany through the Nord Stream 1 pipeline would fall to 33 million cubic metres per day from Wednesday.
European politicians have repeatedly said Russia could cut off gas by coming winter, a step that would thrust Germany into recession, yet they have not agreed on alternative to Russia’s gas.