Moscow Mayor Sergei Sobyanin on Saturday asked people to refrain from trips around the city as far as possible given a counter-terrorism operation had been declared and said the situation was "difficult."

Sobyanin also said in a statement that Monday would be a non-working day - with some exceptions - in order 'to minimise risks.'

He issued the statement as mutinous Wagner mercenary fighters appeared to be continuing to drive towards Moscow from southern Russia.