Jailed Russian opposition politician Alexei Navalny on Tuesday confirmed his arrival at what he described as a snow-swept prison above the Arctic Circle and said he was in excellent spirits despite a tiring 20-day journey to get there.

Navalny posted an update on social media platform X via his lawyers after his allies lost touch with him for more than two weeks while he was in transit with no information about where he was being taken, prompting expressions of concern from Western politicians.

His spokeswoman said on Monday that Navalny, 47, was tracked down to the IK-3 penal colony north of the Arctic Circle located in Kharp in the Yamal-Nenets region about 1,900 kilometres northeast of Moscow.

“I am your new Father Frost,” Navalny wrote jokingly in his first post from his new prison, a reference to the harsh weather conditions there.

“Well, I now have a sheepskin coat, an ushanka hat (a fur hat with ear-covering flaps), and soon I will get valenki (traditional Russian winter footwear).

“The 20 days of the transfer were quite tiring, but I’m still in an excellent mood, as Father Frost should be.”

Navalny’s new home, known as “the Polar Wolf” colony, is considered to be one of the toughest prisons in Russia. Most prisoners there have been convicted of grave crimes. Winters are harsh and temperatures are due to drop to around minus 28 degrees Celsius there over the next week.

About 60km north of the Arctic Circle, the prison was founded in the 1960s as part of what was once the GULAG system of forced Soviet labour camps, according to the Moskovsky Komsomolets newspaper.

Navalny, who thanked his supporters and everyone else for their concern about his welfare during his long transfer, said he had seen guards with machineguns and guard dogs and had gone for a walk in the exercise area which he said was located in a neighbouring cell, the floor of which he said was covered with snow.

Otherwise, he said he had just seen the perimeter fence out of a cell window.

“Anyway, don’t worry about me. I’m fine. I’m awfully glad I finally made it here,” said Navalny.