UN Secretary-General Antonio Guterres continues to push for a halt in hostilities in Ukraine even though a Russian UN envoy said a cease-fire is not a good option at the moment, said a UN spokesman.

"We continue to call for a cease-fire or some sort of pause. The secretary-general did that, as you know, just last week. Clearly, that didn't happen in time for (Orthodox) Easter," said Farhan Haq, deputy spokesman for Guterres.

"I don't want to give too many details at this stage of the sort of proposals he will have. I think we're coming at a fairly delicate moment. It's important that he is able to talk clearly with the leadership on both sides and see what progress we can make," he told a daily press briefing.

"Ultimately, the end goal is to have a halt to fighting and to have ways to improve the situation of the people in Ukraine, lessen the threat that they're under, and provide humanitarian aid (to) them. So, those are the goals we're trying, and there are certain ways that we'll try to move those forward," he said.

Guterres was on his way to Moscow from Turkey. He will have a working meeting and lunch with Russian Foreign Minister Sergei Lavrov on Tuesday, and will be received by President Vladimir Putin. Guterres then will travel to Ukraine and have a working meeting with Ukrainian Foreign Minister Dmytro Kuleba, and will be received by President Volodymyr Zelensky on Thursday.

Before his trips to Moscow and Kiev, Guterres made a stop-over in Turkey, where he met President Recep Tayyip Erdogan over the Ukraine issue.

Haq said the secretary-general is making the trips because he thinks there is an opportunity now.

"A lot of diplomacy is about timing, about finding out when is the right time to speak with a person, to travel to a place, to do certain things. And he is going in the anticipation that there is a real opportunity that is now availing itself, and we'll see what we can make of it," he said.

Dmitry Polyanskiy, Russia's first deputy permanent representative to the United Nations, said Monday that now is not the time for a cease-fire.

"We don't think that cease-fire is a good option right now. The only advantage it will present is that it will give Ukrainian forces a possibility to regroup and stage more provocations like the one in Bucha," he told reporters. "It is not up to me to decide, but I do not see any reason in this right now."