U.S. and Russian negotiators on Monday sat down for talks in Saudi Arabia on a partial ceasefire in Ukraine, hours after a round of negotiations between U.S. and Ukrainian delegations, Russian news reports said. 

The state Tass and RIA-Novosti news agencies said the negotiations had begun in the capital Riyadh. The meeting is expected to be followed by another contact between U.S. and Ukrainian teams. 

The separate meetings are set to discuss details of a pause in long-range attacks from both Russia and Ukraine against energy facilities and civilian infrastructure, as well as a halt on attacks in the Black Sea to ensure safe commercial shipping. 

Ukraine and Russia have agreed in principle to a limited ceasefire after U.S. President Donald Trump spoke with the countries' leaders. But the parties have offered different views of what targets would be off-limits to attack and accused each other of undermining efforts to reach a pause in fighting that started when Russia invaded Ukraine in February 2022.

WATCH l Wise to start with limited ceasefire, former defence department official says: 

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Russia, Ukraine exchange accusations

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 said he would also like railways and ports to be protected. 

Kremlin spokesperson Dmitry Peskov emphasized Friday that the agreement reached between Trump and Putin referred only to energy facilities, adding that the Russian military is fulfilling Putin's order to halt such attacks for 30 days. Peskov accused Ukraine of derailing the partial ceasefire with an attack on a gas metering station in Sudzha in Russia's Kursk region. Ukraine's military General Staff rejected Moscow's accusations and blamed the Russian military for shelling the Sudzha gas metering station, a claim Peskov rejected as "absurd." 

In a televised statement Sunday evening, Zelenskyy said that "since March 11, a proposal for an unconditional ceasefire has been on the table, and these attacks could have already stopped. But it is Russia that continues all this." 

"There must be more pressure on Russia to stop this terror," Zelenskyy said, adding that it "depends on all our partners — the U.S., Europe, and others around the world."

Zelenskyy has emphasized that Ukraine is open to a full, 30-day ceasefire that Trump has proposed, while Russian President Vladimir Putin has made a complete ceasefire conditional on a halt of arms supplies to Kyiv and a suspension of Ukraine's military mobilization — demands rejected by Ukraine and its Western allies. 

'Constructive talks' so far: Zelenskyy

As for Sunday talks in Riyadh between Ukrainian and U.S. representatives, Zelenskyy said they had been conducted on a more "technical level" compared to similar meetings last week, this time involving representatives from Ukraine's military, energy ministry and diplomatic corps. 

"Our team is working in a fully constructive manner, and the discussion is quite useful. The work of the delegations continues," Zelenskyy said. "But no matter what we're discussing with our partners right now, Putin must be pushed to issue a real order to stop the strikes, because the one who brought this war must be the one to take it back." 

Ukrainian state railway operator Ukrzaliznytsia came under a "massive targeted cyber attack" on its online services on Sunday, the company wrote on Telegram, adding that the restoration of its systems was ongoing as of Monday morning. The company said the cyberattack did not affect train movements or schedules, but that the online purchase of tickets was currently unavailable.

Russian troops fired 99 strike and decoy drones into Ukraine overnight Sunday, according to Ukraine's air force, of which 57 were shot down and 36 were lost from radar. The remaining drones caused damage in at least five regions of Ukraine, the air force report says. 

In the Kharkiv region, a Russian drone struck a residential building in the village of Velyka Babka, injuring a 25-year-old man and a pregnant woman. Both were hospitalized, regional head Oleh Syniehubov said on Telegram on Monday morning.

In the Kyiv region, one man suffered shrapnel injuries overnight as a Russian drone struck a residential area, officials said.