Turkish President Tayyip Erdogan has written to Russian leader Vladimir Putin to apologize for the downing of a Russian air force jet by Turkey's military, the Kremlin said Monday.

In a statement, the Kremlin said Putin had received a letter from Erdogan "in which the Turkish leader expressed his desire to resolve the situation connected to the downing of a Russian military aircraft."

Moscow imposed trade restrictions on Ankara after a Russian Su-24M bomber was shot down by a Turkish fighter jet near the Syria-Turkey border on November 24, and Putin has said the sanctions would not be lifted unless Erdogan apologized for the incident.

"The letter states, in particular, that Russia is a friend to Turkey and a strategic partner, with which the Turkish authorities would not wish to spoil relations," the Kremlin's statement continued.

There was no immediate comment from Ankara.

The Kremlin cited Erdogan as saying in the letter, "I want to once again express my sympathy and deep condolences to the family of the Russian pilot who died and I say, 'I'm sorry.'"

The Turkish lira firmed to 2.93 against the US dollar from 2.94 beforehand after the Kremlin said Erdogan had expressed his regret.

According to Turkey, the Russian aircraft involved in the incident - the nationality of which was unknown at the time - was fired upon while in Turkish airspace because it crossed 2.19 kilometers over the border for about 17 seconds after being warned to change its heading 10 times as it approached the border.

The plane crashed in the mountainous Jabal Turkmen area of the Syrian province of Latakia, which is contested by the Syrian government and rebel forces. The Russian pilot and a marine sent on a rescue mission by helicopter were killed.

Russia's Defense Ministry later denied that the aircraft ever left Syrian airspace, countering that their satellite data showed the jet was about 1,000 meters inside Syrian airspace when it was shot down.

The Turkish military published what it said was the radar image of the path the Russian plane took, showing it briefly flying across Turkey's southernmost tip.