KYIV, Ukraine (AP) — Foreign analysts say Russia may be temporarily easing its offensive in eastern Ukraine as the Russian military attempts to reassemble its forces for a significant – and what it hopes could prove decisive – offensive to conquer the neighboring country.

On Wednesday, Russian forces made no claimed or assessed territorial gains in Ukraine “for the first time in 133 days of war,” according to the Institute for the Study of War. The think tank based in Washington suggested that Moscow may be taking an “operational pause,” but that it does not entail “the complete cessation of active hostilities.”

“Russian forces will likely confine themselves to relatively small-scale offensive actions as they attempt to set conditions for more significant offensive operations and rebuild the combat power needed to attempt those more ambitious undertakings,” the institute said.

A Thursday statement from Russia’s Defense Ministry seemed to confirm that assessment. It said Russian military units involved in combat in Ukraine had been given time to rest.

“The units that performed combat missions during the special military operation are taking measures to recover their combat capabilities. The servicemen are given the opportunity to rest, receive letters and parcels from home,” read the statement, quoted by Russian state news agency Tass.

Ukrainian President Volodymyr Zelenskyy met with two U.S. senators in Kyiv on Thursday, according to a statement from his office, which published images of the president with U.S. Sens. Lindsey Graham, a Republican from South Carolina, and Richard Blumenthal, a Democrat from Connecticut.

Zelenskyy spoke with them about Ukraine needing more air defenses before the scheduled start of its school year in September, the president’s office said.

“We count on the support of Congress in the issue of supplying modern air defense systems,” the statement said. “We must ensure such a level of security in the sky that our people are not afraid to live in Ukraine.”

Shelling in Ukraine’s east killed at least nine civilians and wounded six in 24 hours between Wednesday and Thursday, Ukrainian officials said.

The presidential office said in its morning update that cities and villages in seven of the country’s regions were shelled in the past day. Most of the civilian deaths occurred in Donetsk province, where fighting is ongoing. Seven civilians were killed there, including a child, the presidential office said.

Later Thursday, a missile hit a residential area in the Donetsk city of Kramatorsk, killing one civilian and injuring at least six, officials said. Burning cars and broken trees smoldered at the scene of the strike, which left a crater in the center of a courtyard.

Volodymyr, 66, a resident who declined to provide his full name, sat in his overturned apartment, covered in blood.

“I was just sitting and drinking tea, and then there was an explosion,” he told Associated Press journalists. “You can see the result of it.”

Asked if he felt safe staying in his Kramatorsk apartment building block, he responded: “Is it safe right now anywhere in Ukraine? It all just happened in one moment, and that was it.”

In all, 10 cities and villages came under shelling in Donetsk, and 35 buildings were destroyed, including a school, a vocational college and a hospital, officials said.

Donetsk is part of the Donbas, a mostly Russian-speaking industrial region where Ukraine’s most experienced soldiers are concentrated. Pro-Russian separatists have fought Ukrainian forces and controlled much of the Donbas for eight years. Russian President Vladimir Putin recognized the independence of two self-proclaimed republics there just before Russia invaded Ukraine on Feb. 24.

Putin on Monday claimed victory in Luhansk, the other province constituting the Donbas, after Ukrainian forces withdrew from the last city they controlled there. The governor of Luhansk, Serhiy Haidai, denied Wednesday that the Russians had completely captured the province.

In Kharkiv, Ukraine’s second-largest city, a boarding school was hit, but no one was injured. The Kharkiv region, which lies along the border with Russia, is under daily shelling, and two civilians were killed there over the past 24 hours.

Even as the fighting continued, the British Defense Ministry said it thinks Russia’s military is “reconstituting” its forces. A ministry intelligence assessment issued Thursday said the heavy shelling along the front line in Donetsk is likely intended to secure previous Russian gains.

Further hostilities were reported in the Black Sea. The Ukrainian military said Thursday a national flag again stood on a strategic island that Russian troops withdrew from last month.

Ukraine’s Operational Command South said in a statement that Ukrainian military units had cleared Snake Island, an outpost off Ukraine’s southwestern coast vital for guaranteeing sea lanes out of Odesa, home to Ukraine’s biggest port.

The command group said that in addition to planting Ukraine’s flag on the island, the Ukrainian military also destroyed left behind Russian military equipment, describing the discovery of “abandoned ammunition and vast ruins.”

The Russian Defense Ministry said Thursday that a Russian military aircraft launched a missile strike on the island as Ukrainian forces attempted to plant the flag. “As a result, some of the Ukrainian military personnel were destroyed, the rest fled,” the ministry said. The claim could not be immediately verified.

When Russian troops withdrew from Snake Island on June 30, the Defense Ministry described it as a “a goodwill gesture” to ensure Ukrainian grain and other exports could resume.

Ukraine said Russia also fired two missiles targeting a Moldovan-flagged oil tanker in the Black Sea, setting it ablaze.

Ukraine’s southern military command said the strike hit the Millennial Spirit, which carried over 500 tons of diesel fuel. Ukrainian officials said one missile struck the ship, while the other went wide. Social media images showed smoke rising off the coast of Odesa on Thursday morning.

The ship has been without a crew, drifting at sea since the start of the war in February. Russia did not immediately acknowledge the strike on the vessel. The ship’s tracking devices have been down since it was abandoned by its crew.