With its hopes for a speedy triumph dashed by robust Ukrainian opposition, Russia has shifted its attention to grinding down Ukraine’s troops in the east in the hopes of compelling Kyiv to give a portion of the country’s territory and so bring the conflict to a close.

The majority of the Ukrainian army is stationed in eastern Ukraine, where it has been battling rebels supported by Moscow for for eight years. If Russia is successful in surrounding and killing Ukrainian forces in Donbas, Ukraine’s industrial heartland, it may try to impose conditions to Kyiv and possibly divide the nation in half.

The “first stage of the operation,” according to the Russian military, has been mostly completed, letting Russian soldiers to focus on their “primary aim – the liberation of Donbas.”

Many analysts believe the shift in approach reflects President Vladimir Putin’s recognition that his blitz in Ukraine failed, forcing him to focus his aims and alter tactics in the midst of a devastating conflict that has transformed Russia into a pariah state and wrecked its economy.

Officials from the United States and the United Kingdom have also underlined that Moscow has shifted its attention to attacking Ukrainian forces in the east, digging in around Kyiv and other major cities and bombarding them with rockets and artillery.

According to Kyrylo Budanov, the head of Ukrainian military intelligence, the shift in focus might indicate Putin’s desire to split Ukraine in two, like North and South Korea, and establish “a line of demarcation between the occupied and unoccupied territories.”

“He can’t consume the whole nation,” Budanov said, adding that Russia looks to be attempting to “combine the seized areas into a single quasi-state structure, pitting it against sovereign Ukraine.”

Putin and his generals haven’t divulged particular military objectives or a timetable, but as Russian forces moved into Ukraine from the north, east, and south on Feb. 24, the Kremlin evidently expected a rapid triumph.

However, Russian attempts to quickly seize Kyiv, Ukraine’s capital, Kharkiv, and other major cities in the northeast have been foiled by well-organized Ukrainian defenses and logistical problems, causing the Russian operation to stall.

Russian forces have bombarded the outskirts of Kyiv with artillery and air attacks from afar, putting their ground offensive on hold, a technique they have already used in the northeastern cities of Kharkiv, Chernihiv, and Sumy.

Ukrainian military have forced the Russians back in certain areas, notably Makariv, which is located on a critical route west of Kyiv.

After the combat there a few days ago, Associated Press reporters observed the carcass of a Russian rocket launcher, a burnt Russian vehicle, the body of a Russian soldier, and a wrecked Ukrainian tank. The AP saw fortifications abandoned by Ukrainian forces who had retreated farther west in the neighboring settlement of Yasnohorodka, but no trace of Russian troops.

According to Mykola Sunhurovskyi, a military expert at the Razumkov Center think tank in Kyiv, Russia has given up on storming Kyiv and other major Ukrainian cities for the time being and is instead laying siege to them in order to weaken Ukraine and buy time.

“Russia has changed tactics,” Sunhurovskyi stated, “to rearrange its forces and prepare for the next active stage of the fight.”

Russian soldiers ringed and besieged Mariupol, a crucial strategic port, for weeks, pounding it with rockets and artillery in a massacre that killed hundreds of people. The fall of Mariupol would free up Russian soldiers in the area, allowing them to join up with another set of troops advancing from Kharkiv in the northeast to try to encircle the Ukrainian military in the east in a possible pincer operation.

“Russian troops appear to be concentrating their efforts to encircle Ukrainian forces directly confronting separatist territories in the east of the nation, moving from the directions of Kharkiv in the north and Mariupol in the south,” the British Ministry of Defense stated on Sunday.

The recent Russian focus on Donbas was also mentioned by a senior US defense official. Putin may now try to convince Ukrainian President Volodymyr Zelenskyy to legally transfer control of Donbas and accept Russia’s sovereignty of Crimea, which Moscow acquired in 2014.

The extent to which the Russians can push an accelerated move to cut off Donbas will depend in part on how quickly their forces gain full control of Mariupol and how badly damaged they emerge from that fight, according to a report released Saturday by the Institute for the Study of War in Washington. A stop in the Russian onslaught on Kyiv might indicate “Russian troops’ inability more than any alteration in Russian intentions or efforts at this moment,” according to the report.

While the Russian military has been concentrating its efforts on the east to bleed Ukrainian forces, it has continued to employ its stockpile of air and sea-launched cruise missiles to target fuel depots, military arsenals, and weapons industries across the country.

The cruise missile strikes on Lviv near the Polish border on Saturday, according to Philips P. Obrien, a professor of strategic studies at the University of St. Andrews, were part of a Russian plot to cut off supplies to Ukrainian forces fighting in the east.

“They’ll still seek to impede as much as possible the movement of products and resources from west to east,” Obrien said.

The Russians rapidly conquered the Black Sea port of Kherson and moved to the suburbs of Mykolaiv, a significant shipbuilding facility, where their onslaught stopped.

If Russian forces succeed in surrounding Mykolaiv, Odesa, and many other Black Sea ports, Ukraine’s access to its coast will be entirely shut off, dealing a severe blow to the country’s economy. Moscow will be able to build a link to the separatist Trans-Dniester area of Moldova, which is home to a Russian military base, as a result of the annexation of Odesa.

Despite worries from Ukraine and the West, the Russian army has so far refrained from bypassing Mykolaiv and marching on Odesa. Russia’s unwillingness to pursue its advance along the coast, according to Ukrainian authorities, might be explained by the fact that most of its forces in the south are still engaged in the struggle for Mariupol, where they have sustained serious losses.

Since the start of the battle, the Russian military has recorded 1,351 soldiers killed and 3,825 injured, while NATO estimates 7,000 to 15,000 died – perhaps as many as the Soviet Union lost in the whole 10-year war in Afghanistan.

The Russian offensive’s large casualties and poor pace may have prompted Putin to scale down his aspirations and adopt a more pragmatic strategy.

Russia’s announced move to the east, according to Volodymyr Fesenko, the chairman of the independent Penta Center in Kyiv, might be an attempt to put a positive spin on its unsuccessful blitz and recuperate before the next round of battle.

“Both sides are in need of a pause right now for various reasons,” Fesenko told reporters. “The Kremlin is utilizing it to reorganize its forces and hunt for new methods without abandoning its strategic aim of subduing Ukraine.”

“Tactics might shift from a blitz to laying siege to towns, bombarding cities to destroy the economy and infrastructure, blockading ports, and other tactics.” Putin has a large array of pressure tools at his disposal.”

“If the battle in Ukraine turns into a lengthy confrontation, the question of financial and military resources, especially the bombers and tanks that Zelenskyy is pressing the West to deliver, would become paramount,” he warned.