Moscow has warned Donald Trump against resuming the testing of nuclear weapons when he takes office, saying it would “not rule anything out” in response to US aggression.

Azerbaijani intelligence has blamed Russia for the crash, with Euronews reporting on intelligence from anonymous Azerbaijani government sources that said the plane was not given permission to land in Russia despite requesting an emergency landing.

White House spokesman John Kirby has said the US has seen "early indications" that Russia may have been responsible for the downing of the Azerbaijan Airlines plane that crashed on 25 December, killing 38 people.

Putin’s escalating campaign against immigrants has tapped a well of ethnic hatred.

The State Department says an American schoolteacher arrested in Russia on drug charges more than four years ago has been designated by the U.S. government as wrongfully detained.

Five months after their shock offensive into Russia, Ukrainian troops are bloodied by daily combat losses and demoralized by the rising risk of defeat in Kursk.

Marc Fogel has been designated as "wrongfully detained" by the United States government, according to the U.S. Department of State.

The long-range missiles provided by the United States and Britain were used to strike inside Russian territory, despite concerns that their use would escalate the conflict. Kyiv’s stockpiles are running out.

The apology from Russian President Putin came as allegations mounted that the plane had been shot down by Russian air defenses.

The Kremlin said Putin had "offered his apologies that the tragic incident had occurred in Russia's airspace."