KYIV, Ukraine (AP) — Top American officials pledged Monday to help ensure Ukraine wins its fight against Russia following face-to-face talks with President Volodymyr Zelenskyy in Kyiv, while Britain said Moscow has yet to achieve a significant breakthrough in its offensive in Ukraine’s eastern industrial heartland.

In meetings with Zelenskyy, U.S. Secretary of State Antony Blinken and U.S. Defense Secretary Lloyd Austin said the United States had approved a $165 million sale of ammunition for Ukraine’s war effort, along with more than $300 million in foreign military financing.

“The strategy that we’ve put in place — massive support for Ukraine, massive pressure against Russia, solidarity with more than 30 countries engaged in these efforts — is having real results,” Blinken told reporters in Poland the day after meeting with Zelenskyy and other Ukrainian officials.

“When it comes to Russia’s war aims, Russia is failing. Ukraine is succeeding. Russia has sought as its principal aim to totally subjugate Ukraine, to take away its sovereignty, to take away its independence. That has failed.”

As fighting continued, Russia struck deep into Ukraine, targeting infrastructure far from the front line, according to Ukrainian and Russian reports.

In a series of strikes on Ukraine’s railways, a Russian missile hit one facility near Krasne, outside the western city of Lviv, early Monday, sparking a fire, the region’s governor said. A total of five railways facilities in central and western Ukraine were hit by Russian strikes, said Oleksandr Kamyshin, the head of the state-run Ukrainian Railways.

Meanwhile, Serhiy Borzov, the governor of Ukraine’s central Vinnytsia region, said there were casualties after rocket strikes targeting “critical infrastructure.” It was not clear if those strikes were related to the attacks on the railways.

Russia also destroyed an oil refinery in Kremenchuk in central Ukraine, along with fuel depots there, Russian Defense Ministry spokesman Maj. Gen. Igor Konashenkov said Monday.

He added that other strikes by long-range missiles overnight hit concentrations of troops and weapons and ammunition depots in Barvinkove and Nova Dmytrivka in the Kharkiv region, near the Russian border. In all, he said Russian warplanes destroyed 56 Ukrainian targets.

To Ukraine’s north, in the Russian region of Bryansk, a fire erupted early Monday at an oil depot, but no immediate cause was given for the blaze in oil storage tanks.

NASA satellites that track fires showed something burning at coordinates that corresponded to a Rosneft facility some 110 kilometers (70 miles) north of the Ukrainian border. Moscow previously has blamed Ukraine for attacks in Bryansk.

Following the meeting with Blinken and Austin, Zelenskyy said he was “very thankful” for the American aid and particularly praised U.S. President Joe Biden for his “personal support.”

“The priorities are weapons and support from the United States of America and our partners, European leaders, in terms of our army’s strength and support in certain areas,” the Ukrainian president said. “The second issue is the sanctions policy against the Russian Federation because of the full-scale invasion and all the terror they have committed in Ukraine.”

The three-hour meeting came Sunday, the 60th day since the start of the invasion, as Ukraine pressed the West for more powerful weapons against Russia’s campaign in the Donbas region of eastern Ukraine, where Moscow’s forces sought to dislodge the last Ukrainian troops in the battered port city of Mariupol.

Britain’s Ministry of Defense said Monday that Ukrainian troops holed up in a steel plant in the strategic city were tying down Russian forces, and keeping them from being added to the offensive elsewhere in the Donbas.

“Many Russian units remain fixed in the city and cannot be redeployed,” the ministry said in a statement posted on Twitter. “Ukraine’s defense of Mariupol has also exhausted many Russian units and reduced their combat effectiveness.”

The ministry added that, so far, Russia has only made “minor advances in some areas since shifting its focus to fully occupying the Donbas.”

“Without sufficient logistical and combat support enablers in place, Russia has yet to achieve a significant breakthrough,” the ministry said.

With Russia’s shift in focus, Austin said Ukraine’s military needs are changing, and Zelenskyy is now focused on more tanks, artillery and other munitions.

“The nature of the fight has evolved, because the terrain they’re now focused on is a different type of terrain, so they need long-range fires,” Austin said.

Asked about what the U.S. sees as success, Austin said that “we want to see Ukraine remain a sovereign country, a democratic country able to protect its sovereign territory, we want to see Russia weakened to the point where it can’t do things like invade Ukraine.”

On the diplomatic front, U.N. Secretary-General Antonio Guterres was scheduled to travel to Turkey on Monday and then Moscow and Kyiv. Zelenskyy said it was a mistake for Guterres to visit Russia before Ukraine.

“Why? To hand over signals from Russia? What should we look for?” Zelenskyy said Saturday. “There are no corpses scattered on the Kutuzovsky Prospect,” he said, referring to one of Moscow’s main avenues.

Blinken said he had spoken with Guterres on Friday ahead of the trip.

“Our expectation is that he’s going to carry a very strong and clear message to Vladimir Putin, which is the need to end this war now,” he said.

In a boost in support for Ukraine, French President Emmanuel Macron comfortably won a second term Sunday over far-right challenger Marine Le Pen, who had pledged to dilute France’s ties with the European Union and NATO. Le Pen had also spoken out against EU sanctions on Russian energy and had faced scrutiny during the campaign over her previous friendliness with the Kremlin.

Since failing to capture Kyiv, the Russians have aimed to gain full control over the Donbas, the eastern industrial heartland, where Moscow-backed separatists controlled some territory before the war.

For the Donbas offensive, Russia has reassembled troops who fought around Kyiv and in northern Ukraine. The British Ministry of Defense said Ukrainian forces had repelled numerous assaults in the past week and “inflicted significant cost on Russian forces.”

In the south of the Donbas, in the strategic port city of Mariupol, a small pocket of Ukrainian troops continues to hold out against Russian forces in the Azovstal steel factory, a sprawling facility on the waterfront.

Mariupol has endured fierce fighting since the start of the war because of its location on the Sea of Azov. Its capture would deprive Ukraine of a vital port, free up Russian troops to fight elsewhere, and allow Moscow to establish a land corridor to the Crimean Peninsula, which it seized from Ukraine in 2014.

Over the weekend, Russian forces launched fresh airstrikes on the steel plant in an attempt to dislodge the estimated 2,000 fighters inside. An estimated 1,000 civilians are also sheltering in the factory.

New satellite images by Planet Labs PBC, taken Sunday, show destroyed buildings across the steelworks and smoke rising from one area. Roofs have gaping holes; a soccer field is cratered from incoming fire.

More than 100,000 people — down from a prewar population of about 430,000 — are believed to remain in Mariupol with scant food, water or heat. Ukrainian authorities estimate more than 20,000 civilians have been killed. Recent satellite images showed what appeared to be mass graves to the west and east of Mariupol.