The Russian ruble edged up against the dollar in thin on- and offshore trading on Friday, but ended a third week of hefty losses, with the central bank now further restricting access to foreign currency.

The ruble has lost a third of its value in Moscow exchanges since Russia invaded Ukraine last month, as the local economy buckles under the pressure of sanctions imposed across the world in retaliation for the invasion.

President Volodymyr Zelensky said Ukraine had reached a "strategic turning point" in the conflict with Russia, but Russian forces bombarded cities across the country in what Moscow refers to as a "special operation," and appeared to be regrouping for a possible assault on the capital Kyiv.