Kiev/Moscow, 14 May 2024 (dpa) - Ukrainian President Volodymyr Zelensky asked visiting US Secretary of State Antony Blinken on Tuesday for Patriot air defence systems for the city of Kharkiv despite Kiev officials saying there had been a slight "stabilization" at the front.

Russia launched a major attack in the border region near Ukraine's second-biggest city four days ago, already capturing several Ukrainian villages, while it continues to bombard Kharkiv with missiles.

Two Patriot systems are necessary to protect the north-eastern city and its surrounding area, which borders Russia, Zelensky said in Kiev during Blinken's surprise visit.

US assistance for the campaign against the Russians was of crucial importance and air defence was the "biggest deficit," Zelensky added.

According to Ukrainian media reports, Blinken promised Ukraine weapons aid that could change the situation on the battlefield.

Blinken said on X: "I returned to Kyiv (Kiev) today to demonstrate our unwavering support for Ukraine as they defend their freedom against Russian aggression."

The visit, which as usual was not announced for security reasons, is Blinken's fourth since the start of the war in February 2022 and is also the first visit since the US approved a long-delayed aid package of $61 billion.

Ukraine has been on the defensive for months due to a lack of weapons, ammunition and soldiers.

Last week's renewed Russian assault spooked Kiev and the West.

The situation in the Kharkiv area remains very tense and is changing rapidly, the head of Ukraine's HUR military intelligence service, Kyrylo Budanov, said in a TV news update.

"But I believe that there has been a rapid tendency towards stabilization since yesterday evening," he added. 

In Moscow, the Defence Ministry reported that Russian troops had captured the village of Buhruvatka in addition to land seized earlier and had repelled all Ukrainian counter-attacks.

According to US military experts, however, Russian forces advancing near Kharkiv will likely limit their push to the rapid creation of a buffer zone between the two countries.

That goal is apparently being prioritized over a deeper offensive into the Kharkiv region, the Washington-based Institute for the Study of War (ISW) wrote in its latest report on Monday.

Despite the situation in Kharkiv, Ukraine appears to be continuing its policy of hitting targets inside Russia.

Explosions were heard in the Russian border region of Belgorod following a missile alert, the Russian state agency TASS reported.

The Russian Ministry of Defence announced that air defence systems had shot down 25 missiles over the region.

This information, like most announcements during the war, could not initially be independently verified.

Meanwhile, a goods train was derailed by a suspected Ukrainian drone attack in the south-western Russian region of Volgograd, a Russian media report said.

The drone crashed into the fuel tank, the Baza Telegram channel reported, although the press service of the Russian railways simply said outside interference had caused the incident.

"According to preliminary information, there are no injuries," it added in a statement.

The derailed train damaged 300 metres of track near the village of Kotluban. Videos on social media showed derailed wagons scattered across the tracks. Some of them were badly damaged.

It took several hours before one lane of the line could be reopened.

Kotluban is located more than 300 kilometres from the Ukraine border.

MIA file photo