*

Putin vows worthy response

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Russia evacuates part of Belgorod region

*

Ukraine poses threat to another Russian region, governor

says

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Russia has stabilised fighting in Kursk, bloggers say

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Fire at Russian-controlled Zaporizhzhia nuclear plant

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Rouble 6% weaker versus dollar since border

incursion

(Recasts with Putin)

By Guy Faulconbridge

MOSCOW, Aug 12 (Reuters) - Russian President Vladimir

Putin said on Monday that the army would eject Ukrainian troops

from Russian sovereign territory after Kyiv's biggest incursion

across the border since the start of the war in 2022.

Ukrainian forces rammed through the Russian border last

Tuesday and swept across some western parts of Russia's Kursk

region, a surprise attack that may be aimed at gaining leverage

in possible ceasefire talks after the U.S. election in November.

Apparently caught by surprise, Russia by Sunday had

stabilised the front in the Kursk region, though Ukraine had

carved out a sliver of Russian territory where battles were

continuing on Monday, according to Russian war bloggers.

In the neighbouring Belgorod region to the south, regional

governor Vyacheslav Gladkov said evacuations of civilians had

begun from the Krasnaya Yaruga District due to "enemy activity

on the border".

Putin, in his most detailed remarks on the incursion to

date, said that Ukraine "with the help of his Western masters"

was trying to improve its negotiating position ahead of possible

ceasefire talks and to undermine Russian advances.

Putin told security officials and regional governors that

the Ukrainian forces were suffering heavy casualties in their

incursion.

"The enemy will certainly receive a worthy response, and all

the goals facing us will, without a doubt, be achieved."

Putin said Ukraine was trying to intimidate Russian society

and thus undermine stability. He warned senior officials that

Ukraine would seek to further destabilise border regions.

At the Putin meeting, the acting governor of Kursk, Alexei

Smirnov, said Ukraine controlled 22 settlements in the region,

and that the incursion was about 12 km deep and 40 km wide.

Russia has imposed tight security in the Kursk, Bryansk and

Belgorod regions while its ally Belarus said it was bolstering

its troop numbers at its border after Minsk said Ukraine had

violated its airspace with drones.

Russian officials say Ukraine's attacks on Russian territory

are aimed at showing its Western supporters that Kyiv can still

muster major military operations while trying to gain a

bargaining chip ahead of possible ceasefire talks.

Russia invaded Ukraine in February 2022 and now controls 18%

of Ukrainian territory. Russian forces, which have a vast

numerical supremacy, have been advancing this year along the

1,000-km (620-mile) front after the failure of Ukraine's 2023

counteroffensive to make any major gains.

Kyiv broke its silence on the attacks on Saturday when

President Volodymyr Zelenskiy said Ukraine had launched an

incursion into Russian territory to "restore justice" and

pressure Moscow's forces.

At the Zaporizhzhia nuclear power plant, in a part of

Ukraine controlled by Russian forces, a major fire broke out.

GAS HUB

The Ukrainian attack has prompted some in Moscow to question

why Ukraine was able to pierce the Kursk region so easily after

more than two years of the most intense land war in Europe since

World War Two.

Russian war bloggers said Ukrainian forces in Kursk were

trying to encircle Sudzha, where Russian natural gas flows into

Ukraine, while major battles were underway near Korenevo, about

22 km (14 miles) from the border, and Martynovka.

"The situation on the borders of the western Belgorod region

is alarming," said Yuri Podolyaka, an influential pro-Russian

military blogger, adding that Ukraine was probing the border at

several places.

"The enemy has three fairly large groupings here."

Since the Aug. 6 border incursion into Kursk, the Russian

rouble has weakened, losing 6% of its value against the U.S.

dollar. Russia's Gazprom said it would send 39.6 million cubic

metres (mcm) of gas to Europe via Ukraine on Monday.

Though the United States said it had not been told of the

Ukrainian operation before it was unleashed, there were signs in

Moscow that the attack would provoke a response from Russia.

"We have no doubt that the organisers and perpetrators of

these crimes, including their foreign curators, will bear

responsibility for them," said Maria Zakharova, spokeswoman for

the Russian Foreign Ministry.

"A tough response from the Russian Armed Forces will not

take long."