Moscow has not officially contacted Kyiv over peace talks, but Russia would have to fully withdraw its forces in any case for talks to take place, a senior Ukrainian official said on Saturday.

“We have no official request from the Russian side about … negotiations,” Andriy Yermak, the Ukrainian president’s chief of staff, said in English comments made via video link at the Halifax International Security Forum.

Any talks not based on Ukrainian sovereignty and territorial integrity within the bounds of its internationally recognized borders are “unacceptable,” he said.

“The first step that the Russian side must take is to withdraw all Russian troops from Ukrainian territory,” Yermak added.

His comments came a day after Ukrainian President Volodymyr Zelenskyy dismissed the idea of ??a “brief ceasefire” with Russia, saying it would only make things worse.

“Russia is now looking for a brief ceasefire, a pause to regain strength. Someone may call this the end of the war, but such a pause will only aggravate the situation,” the Ukrainian leader said in a speech broadcast at the same security forum.

“Truly real, lasting and honest peace can only be the result of complete destruction of Russian aggression,” Zelenskyy said.

The White House on Friday said only Zelenskyy could decide when to open peace talks with Russia, dismissing the notion that it would urge Kyiv to negotiate an end to the nearly nine-month war sparked by Moscow’s February invasion.

However, General Mark Milley, the top US military officer, has suggested in recent weeks that Kyiv could capitalize on battlefield victories over Moscow’s troops and hold talks to end the conflict.

Milley said on Wednesday that while Ukraine has made important gains, Moscow still controls about 20 percent of the country and that Kiev’s troops are unlikely to force the Russians to leave the country anytime soon.