Russia has refused to guarantee humanitarian access to rescue hundreds of thousands of Ukrainian civilians trapped under bombardment, Ukraine says.
Russia's war in Ukraine entered a third week with none of its stated objectives reached, despite thousands killed, more than two million made refugees and thousands cowering in besieged cities under relentless bombardment.
Ukraine's Foreign Minister Dmytro Kuleba met Russia's Sergei Lavrov in Turkey on Thursday, but said he had secured no promise from him to halt firing so aid could reach civilians.
One of the main humanitarian priorities is evacuating hundreds of thousands of people trapped in the besieged port of Mariupol.
"I made a simple proposal to Minister Lavrov: I can call my Ukrainian ministers, authorities, president now and give you 100 per cent assurances on security guarantees for humanitarian corridors," he said.
"I asked him 'can you do the same?' and he did not respond."
Holding his own simultaneous news conference in a separate room, Lavrov showed no sign of making any concessions, repeating Russian demands that Ukraine be disarmed and accept neutral status.
He said Kyiv appeared to want meetings for the sake of meetings and that a ceasefire was not meant to be on the agenda at the Turkey talks.
Aid agencies say humanitarian aid is most urgently needed in Mariupol, where 400,000 people have been trapped for more than a week with no food, water or power.
The city council said the port had come under fresh air strikes on Thursday morning, a day after Moscow bombed what Ukraine called a functioning maternity hospital there.
Lavrov said the building was no longer used as a hospital and had been occupied by Ukrainian forces.
The Kremlin did not initially repeat that denial and said the incident was being investigated.
Ukrainian President Volodymyr Zelenskiy said Russia's assertion was not true and three people including a child had been killed in the air strike, which occurred despite a ceasefire deal to allow people to flee Mariupol.
The regional governor said 17 people including pregnant women were wounded.
"What kind of country is this, the Russian Federation, which is afraid of hospitals, is afraid of maternity hospitals, and destroys them?" Zelenskiy said in a televised address late on Wednesday, after posting footage of the wreckage.
Ukraine said a convoy trying to reach the city had again been turned back by Russian fire on Thursday, and accused Moscow of deliberately blocking aid.
Daily attempts at a local humanitarian ceasefire have failed since Saturday.
Lavrov repeatedly lashed out at the West, accusing Western countries of inflaming the situation by arming Ukraine.
Asked if the conflict could lead to nuclear war, he said: "I don't want to believe, and I do not believe, that a nuclear war could start."
Russian forces have advanced in the south but have yet to capture a single city in the north or east.
The UK Defence Ministry said on Thursday that a large Russian column northwest of Kyiv had made little progress in more than a week and was suffering continued losses.
Western-led sanctions designed to cut the Russian economy and government from international financial markets have bitten hard, with the rouble plunging and ordinary Russians rushing to hoard cash.
Britain added several Russian businessmen to its blacklist on Thursday, including Roman Abramovich, owner of Chelsea soccer team.
The sanctions would block an attempt to sell the club, but a special licence would let it keep playing.
The White House condemned the hospital bombing as a "barbaric use of military force to go after innocent civilians".
The UN Human Rights body said it was trying to verify the number of casualties.
The incident "adds to our deep concerns about indiscriminate use of weapons in populated areas", it added through a spokesperson.
Australian Associated Press
