Russian troops could be preparing to withdraw from the key city of Kherson, which they have held since March, western officials have said.

Ukraine has been talking up an offensive to capture the city since the summer but progress has been slow and so far they have just retaken some surrounding farmland.

Kherson straddles both sides of the Dnipro river and Russian commanders may be pulling troops back to the eastern side of the river which is easier to defend, reports suggest.