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Russia still battling Ukrainian troops in Kursk

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Ukraine may have control of Sudzha - bloggers

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Putin: this is a major Ukrainian provocation

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Ukraine remains silent about situation

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White House: we had no prior knowledge of attack

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Medvedev: Russia should take all of Ukraine

(Adds Russian parliamentarian in 5th paragraph, situation at

gas transit point in paragraphs 13-15)

By Guy Faulconbridge

MOSCOW, Aug 8 (Reuters) - Russian forces were battling

Ukrainian troops for a third day on Thursday after they smashed

through the Russian border in the Kursk region, an audacious

attack on the world's biggest nuclear power that has forced

Moscow to call in reserves.

In one of the biggest Ukrainian attacks on Russia of the

two-year-old war, around 1,000 Ukrainian troops rammed through

the Russian border in the early hours of Aug. 6 with tanks and

armoured vehicles, covered in the air by swarms of drones and

pounding artillery, according to Russian officials.

Heavy fighting was reported near the town of Sudzha,

where Russian natural gas flows into Ukraine, raising concerns

about a possible sudden stop to transit flows to Europe.

The incursion has come as a shock to Russia, nearly

two-and-a-half years since President Vladimir Putin sent his

army into Ukraine in February 2022.

Putin has cast the Ukrainian offensive as a "major

provocation". Sergei Mironov, leader of a Kremlin-loyal

political party, called it a "terrorist attack" and "the

invasion of an internationally recognised foreign territory".

Kursk's regional acting governor, Alexei Smirnov, said that

thousands of residents had been evacuated.

The White House said the United States - Ukraine's biggest

backer - had no prior knowledge of the attack and would seek

more details from Kyiv.

Russia's defence ministry said on Thursday that the army and

the Federal Security Service (FSB) had halted the Ukrainian

advance and were battling Ukrainian units in the Kursk region.

"Units of the Northern group of forces, together with the

FSB of Russia, continue to destroy armed formations of the Armed

Forces of Ukraine in the Sudzhensky and Korenevsky districts of

the Kursk region, directly adjacent to the Russian-Ukrainian

border," the ministry said.

The Ukrainian military has remained silent on the Kursk

offensive, though President Volodymyr Zelenskiy praised the

Ukrainian army on Thursday for its ability "to surprise" and

achieve results. He did not explicitly reference Kursk.

Some Russian bloggers said Ukraine's forces were pushing

towards the Kursk nuclear power station, which lies about 60 km

(37 miles) northeast of Sudzha.

Yuri Podolyaka, a popular Ukrainian-born, pro-Russian

military blogger, said that there were intense battles about 30

km from the Soviet-era nuclear plant, which supplies a large

swathe of southern Russia with power.

CRITICAL JUNCTURE

Ukraine's energy minister said gas transit via Sudzha was

still functioning, despite reports of hostilities there. Most EU

nations have reduced their dependence on Russian gas, but

Austria is one country that still receives most of its gas via

Ukraine.

The Center for Information Resilience, a non-profit

open-source analysis organisation, said it was unable to

visually confirm any damage to the gas metering station as a

result of the incursion, but had verified significant damage to

the border checkpoint about 500 metres to the south.

"This, combined with footage verified by CIR of several

Russian soldiers surrendering to Ukrainian soldiers near the

entrance of the gas metering plant, makes it likely that the

plant has been affected by the Ukrainian incursion, however, the

level of damage cannot be verified at this time," it said.

The battles come at a crucial juncture in the conflict, the

biggest land war in Europe since World War Two. Kyiv is

concerned that U.S. support could weaken if Republican Donald

Trump wins the November presidential election.

Trump has said he would end the war, and both Russia and

Ukraine are keen to gain the strongest possible bargaining

position on the battlefield.

Ukraine wants to pin down Russian forces, which control 18%

of its territory, though the strategic significance of the

border offensive was not immediately clear.

Former Russian president Dmitry Medvedev said the Ukrainian

attack was an attempt to force Russia to divert resources from

the front and to show the West that Ukraine could still fight.

As a result of the Kursk attack, Medvedev said, Russia

should expand its war aims to include taking all of Ukraine.

"From this moment on, the SVO (Special Military Operation)

should acquire an openly extraterritorial character," Medvedev

said, adding that Russian forces should go to Odesa, Kharkiv,

Dnipro, Mykolayiv, Kyiv "and beyond".

"We will stop only when we consider it acceptable and

profitable for ourselves."

(Additional reporting by Eleanor Whalley in London and

Anastasiia Malenko in Kyiv, Editing by William Maclean)