Ukrainian commander says forces control 1,000sq km of Russia’s Kursk region

General Oleksandr Syrskyi made the statement in a video posted on Monday to Ukrainian President Volodymyr Zelensky’s Telegram channel. In the video, he briefed the president on the front-line situation.

“The troops are fulfilling their tasks. Fighting continues actually along the entire front line. The situation is under our control,” Gen Syrskyi said.

Russian forces are still scrambling to respond to the surprise Ukrainian attack after almost a week of fierce fighting.

Russian President Vladimir Putin has said the Ukrainian army’s incursion into the Kursk region, which has caused more than 100,000 civilians to flee, is an attempt by Kyiv to stop Moscow’s offensive in eastern Ukraine’s Donbas region and gain leverage in possible future peace talks.

Mr Zelensky confirmed for the first time that Ukrainian military forces are operating inside the Kursk region.

On Telegram, he praised his country’s soldiers and commanders “for their steadfastness and decisive actions”.

Mr Zelensky did not elaborate. He also suggested that Ukraine would offer humanitarian assistance in the region.

Speaking at a meeting with top security and defence officials, Mr Putin said the attack that began on August 6 appeared to reflect Kyiv’s attempt to gain a better negotiating position in possible future talks to end the war.

Mr Putin argued that Ukraine may have hoped to cause public unrest in Russia with the attack, adding that it has failed to achieve that goal, and claimed that the number of volunteers to join the Russian military has increased because of the assault.

The president said the Russian military is driving on with its eastern Ukraine offensive regardless.

“It’s obvious that the enemy will keep trying to destabilise the situation in the border zone to try to destabilise the domestic political situation in our country,” Mr Putin said.

Acting Kursk governor Alexei Smirnov reported to Mr Putin that Ukrainian forces had pushed 12 kilometres (7.5 miles) into the Kursk region across a 40-kilometre (25-mile) front and currently control 28 Russian settlements.

Mr Smirnov said 12 civilians have been killed and 121 others, including 10 children, have been wounded in the operation.

About 121,000 people have been evacuated or left the areas affected by fighting on their own, he said.

Tracking down all the Ukrainian diversionary units roaming the region is difficult, Mr Smirnov said, noting that some are using fake Russian IDs.

The governor of the Belgorod region adjacent to Kursk also announced the evacuation of people from a district near the Ukrainian border, describing Monday morning as “alarming” but giving no detail.

Ukrainian forces swiftly rolled into the town of Sudzha about 10 kilometres (six miles) over the border after launching the attack.

They reportedly still hold the western part of the town, which is the site of an important natural gas transit station.

The Ukrainian operation is taking place under tight secrecy, and its goals – especially whether Kyiv’s forces aim to hold territory or are staging hit-and-run raids – remain unclear.

The stunning manoeuvre that caught the Kremlin’s forces unawares counters Russia’s unrelenting effort in recent months to punch through Ukrainian defences at selected points along the front line in eastern Ukraine.

Russia has seen previous incursions into its territory during the nearly two-and-a-half-year war, but the foray into the Kursk region marked the largest attack on its soil since the Second World War, constituting a milestone in the hostilities.

It is also the first time the Ukrainian army has spearheaded an incursion rather than pro-Ukraine Russian fighters.

The advance has delivered a blow to Mr Putin’s efforts to pretend that life in Russia has largely remained unaffected by the war.

State propaganda has tried to play down the attack, emphasising the authorities’ efforts to help residents of the region and seeking to distract attention from the military’s failure to prepare for the attack and quickly repel it.

Kursk residents recorded videos lamenting that they had to flee the border area, leaving behind their belongings, and pleading with Mr Putin for help.

But Russia’s state-controlled media kept a tight lid on any expression of discontent.

Retired general Andrei Gurulev, a member of the lower house of the Russian parliament, criticised the military for failing to properly protect the border.

“Regrettably, the group of forces protecting the border didn’t have its own intelligence assets,” he said on his messaging app channel.

“No-one likes to see the truth in reports, everybody just wants to hear that all is good.”

The combat inside Russia rekindled questions about whether Ukraine was using weaponry supplied by Nato members.

Some Western countries have baulked at allowing Ukraine to use their military aid to hit Russian soil, fearing it would fuel an escalation that might drag Russia and Nato into war.

Though it is not clear what weapons Ukraine is using across the border, Russian media widely reported that US Bradley and German Marder armoured infantry vehicles were there.

It was not possible to independently verify that claim.

Ukraine has already used US weapons to strike inside Russia.

But Italian foreign minister Antonio Tajani said in an interview published on Monday that the weapons provided by his country “cannot be used to attack Russia on its territory”.

Meanwhile, German Defence Ministry spokesperson Arne Collatz said on Monday that legal experts agree that “international law provides for a state that is defending itself also to defend itself on the territory of the attacker. That is clear from our point of view, too”.

Russia’s Defence Ministry said on Monday that reinforcements sent to the area backed by air force and artillery had fended off seven attacks by Ukrainian units near Martynovka, Borki and Korenevo during the previous 24 hours.

The ministry said Russian forces also blocked an attempt by Ukrainian mobile groups to forge deep into the Russian territory near Kauchuk.

Russian air force and artillery also struck concentrations of Ukrainian troops and equipment near Sudzha, Kurilovka, Pekhovo, Lyubimovo and several other settlements, it said.

Warplanes and artillery hit Kyiv’s reserves in Ukraine’s Sumy region across the border, it added.

Pasi Paroinen, an analyst with the Finland-based Black Bird Group open-source intelligence agency, which monitors the war, said the toughest phase of Ukraine’s incursion is likely to begin now as Russian reserves enter the fray.

Ukraine’s progress on Russian territory “is challenging the operational and strategic assumptions” of the Kremlin’s forces, according to the Institute for the Study of War.

It could compel Russia to deploy more military assets to the long border between the two countries, the Washington-based think tank said in an assessment late on Sunday.

It described the Russian forces responding to the incursion as “hastily assembled and disparate”.