U.S. Secretary of State Antony Blinken said Friday that there can be no cease-fire in the war in Ukraine unless it is part of a “just and lasting” peace deal that includes Russia’s military withdrawal.

Blinken said that “a cease-fire that simply freezes current lines in place” and allows Russian President Vladimir Putin “to consolidate control over the territory he has seized, and rest, rearm, and reattack — that is not a just and lasting peace.”

Russia must also pay a share of Ukraine’s reconstruction and be held accountable for launching its full-scale invasion of its neighbor in February 2022, Blinken said in a speech during a visit to Finland, which recently joined NATO and shares a long border with Russia.

Allowing Moscow to keep the one-fifth of Ukraine territory it has occupied would send the wrong message to Russia and to “other would-be aggressors around the world,” according to Blinken.

Washington is ready to support peace efforts by other countries, including recent overtures from China and Brazil, he said. But any peace agreement must uphold the principles of sovereignty, territorial integrity and independence.

The United States is a leading Western ally and supplier of arms to Kyiv to help it push back against the Kremlin’s forces.

China Urges End to Ukraine Weapons Delivery

China, which says it is neutral and wants to serve as a mediator but has supported Moscow politically, on Friday urged countries to stop sending weapons to Ukraine.

In Ukraine, air defenses shot down more than 30 Russian cruise missiles and drones Friday in Moscow’s sixth air attack in six days on Kyiv, local officials said.

The Ukrainian capital was simultaneously attacked from different directions by Iranian-made Shahed drones and cruise missiles from the Caspian region, senior Kyiv official Serhii Popko wrote on Telegram.

A 68-year-old man and an 11-year-old child were wounded in the attack, with private houses, outbuildings and cars sustaining damage from falling debris, according to Ukraine’s Prosecutor General’s Office.

A recent spate of attacks on the capital has put strain on residents and tested the strength of Ukraine’s air defenses while Kyiv officials plot what they say is an upcoming counteroffensive to push back the Kremlin’s forces 15 months after their full-scale invasion. Kyiv was the target of drone and missile attacks on 17 days last month, including daylight attacks.

Moscow’s strategy could backfire, however, according to the Institute for the Study of War, a Washington-based think tank.

The air campaign aims to “degrade Ukrainian counteroffensive capabilities, but … the Russian prioritization of Kyiv is likely further limiting the campaign’s ability to meaningfully constrain potential Ukrainian counteroffensive actions,” it said in an assessment late Thursday.

Ukrainian air defenses intercepted all 15 cruise missiles and 21 attack drones, Ukraine’s chief of staff, Valerii Zaluzhnyi, said.

Ukraine’s presidential office said Friday that at least four civilians were killed and 42 wounded over the previous 24 hours.

Meanwhile, border regions of Russia once again came under fire from Ukraine. Recent cross-border raids have also rattled those regions of Russia and put the Kremlin on guard.

That could be a Ukrainian strategy to disperse Russian forces before a counteroffensive begins.

“Russian commanders now face an acute dilemma of whether to (strengthen) defenses in Russia’s border regions or reinforce their lines in occupied Ukraine,” the U.K. ministry of defense said Friday.

Air defense systems shot down “several Ukrainian drones” overnight Thursday in Russia’s southern Kursk region, which borders Ukraine, regional Gov. Roman Starovoit wrote on Telegram.

In the neighboring Bryansk region, which also borders Ukraine, regional Gov. Alexander Bogomaz said that Ukrainian forces shelled two villages on Friday morning. No casualties were reported.

Two drones also attacked energy facilities in Russia’s western Smolensk region, which borders Belarus, in the early hours of Friday, officials said.