Vladimir Putin has appointed one of his former bodyguards to lead his personal effort to end Ukraine’s invasion of Russia.

Alexei Dyumin, who guarded Putin in his first two terms and is considered a potential successor for the Kremlin leader, was named “Kurator” of the operation to liberate the Kursk region, Russian military bloggers reported on Tuesday.

The move comes after Putin vowed to drive Ukraine off Russian land during a tense meeting with security chiefs on Monday, as Kyiv’s daring cross-border raid entered its seventh day of fighting.

The Kremlin leader appeared to be looking for a scapegoat amongst his top military brass for the Ukrainian operation, the first foreign invasion on Russian soil since the Second World War.

“The appointment of Alexei Dyumin as a senior official with a full range of powers to eliminate the operational crisis in the Kursk region is a sign that on their own and without interference from Moscow the security structures were unable to solve coordination problems,” Rybar, an authoritative Russian military blogger, wrote on the Telegram messaging app.

“Dyumin’s appointment means Putin’s team takes full control of the situation in order to stop the fraud window dressing, and also to begin to solve the problem rather than try to freeze it,” the blogger added.

Dyumin has long been seen as an emerging star in Putin’s entourage, rising to the deputy head of the GRU, Russia’s military intelligence agency, and is thought to have led special forces in the annexation of Crimea in 2014.

He is sanctioned by both the UK and US for his role in the annexation of the occupied peninsula and the current war in Ukraine.

Ukrainian troops crossed the Russian border a week ago, in an operation that Western analysts believe was aimed at improving Kyiv’s negotiating position and diverting Russian resources away from the rest of the front lines.

By Monday evening, Ukrainian forces were in control of around 1,000 square kilometres of Kursk, a border region in southern Russia, according to Kyiv’s top general.

Volodymyr Zelensky, Ukraine’s president, said the invasion would mark the end of Putin’s rule.

Russian war bloggers reported on Tuesday that there were still battles across a widening front as Ukraine tries to expand its area of control near Lgov, which is more than 32 miles north of the Ukrainian-Russian border.

A Ukrainian soldier filmed himself posing in front of the road sign marking the entrance of Lgov, in a video that emerged on social media on Tuesday.

“I hope mama doesn’t see this video; I promised mama I wouldn’t go far away,” he said.

Russian sources also said there were battles for control over Bolshoy Soldatskoye and Korenevo, two towns on the edge of the area Kyiv is believed to be in control of.

One Russian account of the fight near Korenevo said Ukraine was fighting to enter the settlement, which sits on a key highway used by Russia to reinforce its presence in the region.

It also claimed that Russian forces are constructing more than 24 miles of trenches and “90 platoon strongholds” as they dig in to prevent further Ukrainian advances.