Jornal Do Brasilia - Ukraine renews demand to see Russia's peace terms

And as the United Nations said that hopes for peace in the three-year-old war were "barely" alive, the United States again warned that it could withdraw from mediation efforts and impose sanctions on Russia.

Ukraine spoke out after Russia said Thursday it was still waiting for its rival to commit to new talks in Istanbul on Monday.

"Ukraine is ready to attend the next meeting, but we want to engage in a constructive discussion. This means it is important to receive Russia’s draft," President Volodymyr Zelensky's chief of staff, Andriy Yermak, said in a statement in response.

It was not immediately clear whether the statement was setting an official condition for attending the talks.

While diplomatic efforts to end the war have gained pace in recent months, Russia has maintained an intense bombardment of Ukraine and rebuffed calls for an immediate ceasefire.

Moscow has offered to hold a second round of direct talks in Istanbul on June 2, when it said it would present a "memorandum" outlining its conditions for a long-term peace settlement.

Ukraine has repeatedly said the meeting would not yield results unless it saw a copy of the memorandum in advance.

Calling for a response from Ukraine, Kremlin spokesman Dmitry Peskov said Thursday that Kyiv's demand to hand over its "memorandum" was "non-constructive".

Ukraine said it had already submitted its own vision of a peace settlement to Russia and demanded Moscow do the same.

Zelensky said Russia was "doing everything they can to make the meetings empty. And this is another reason why there must be sufficient sanctions, sufficient pressure on Russia."

Moscow's refusal to send the document "suggests that it is likely filled with unrealistic ultimatums", said Ukrainian foreign ministry spokesperson Georgiy Tykhy.

- 'Shut the door' -

Turkey's President Recep Tayyip Erdogan, who would host the new talks, called on Russia and Ukraine not to "shut the door" on dialogue.

Negotiations in Istanbul on May 16 -- the first direct talks on the conflict in more than three years -- yielded only a prisoner exchange and promises to stay in touch.

Russian foreign ministry spokesperson Maria Zakharov told state television the Kremlin planned to send the same negotiating team as for the earlier talks. That was led by Vladimir Medinsky, a Kremlin aide.

After the May 16 talks, Ukraine accused Russia of outlining unrealistic demands, including calls to cede territory Kyiv still controls.

The Russian offensive, launched in February 2022, has resulted in tens of thousands of deaths and the destruction of large parts of eastern and southern Ukraine.

Russian forces have moved forward on the battlefield while pushing peace demands that include Ukraine abandoning its NATO ambitions and giving up around a fifth of its land.

The Russian army said Thursday it had captured three villages in Ukraine's Donetsk and Kharkiv regions in its latest advance.

US President Donald Trump has sought a peace deal but has expressed growing frustration at Russia's stance. He said Wednesday he would determine within "about two weeks" whether Putin was serious about ending the fighting.

At a UN Security Council meeting Thursday, US diplomat John Kelley reaffirmed that Washington could pull back from peace efforts.

"If Russia makes the wrong decision to continue this catastrophic war, the United States will have to consider stepping back from our negotiation efforts to end this conflict," Kelley told the meeting, which included Russian and Ukrainian envoys.

"Additional sanctions" on Russia were possible, he added.

"The hope that the parties will be able to sit down and negotiate is still alive, but just barely," UN under-secretary-general for political affairs Rosemary DiCarlo told the meeting.

Local authorities in Ukraine said Thursday Russia had fired 90 drones overnight.

At least seven people were killed in drone, missile and artillery strikes across five frontline Ukrainian regions, officials said.

Russia said it had repelled 48 Ukrainian drones overnight, including three near Moscow.

Zelensky earlier this week said Russia was "amassing" more than 50,000 troops on the front line around Sumy, where Moscow's army has captured a number of settlements as it seeks to establish what Putin has called a "buffer zone" inside Ukrainian territory.

L.M. Cardoso--JDB