United States and Russian negotiators on Monday worked on a proposed partial ceasefire in the 3-year-old war in Ukraine, a day after holding separate talks with a team from Kyiv.

It has been a struggle to work out even a limited, 30-day ceasefire.

Although Moscow and Kyiv agreed to a truce in principle last week, both sides have continued to attack each other with drones and missiles.

After US President Donald Trump spoke with the countries’ leaders, a key sticking point is what targets would be off-limits to strike.

While the White House said “energy and infrastructure” would be covered, the Kremlin declared that the agreement referred more narrowly to “energy infrastructure.”

Ukrainian President Volodymyr Zelenskyy has said he wants other infrastructure like railways and ports to be protected.

While the talks took place at a luxury hotel in Riyadh, lasting 12 hours, nearly 90 people including 17 children were wounded in a Russian missile attack Monday on Sumy in northeastern Ukraine.

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