Adds detail, background

MOSCOW, Dec 24 (Reuters) - Russian President Vladimir Putin has extended by one year the deadline for the sale of U.S. oil major ExxonMobil's XOM.N stake in the Sakhalin-1 oil and gas project until January 1, 2027, according to a decree published on Wednesday.

The extension is expected to help Exxon recover losses incurred in Russia after it exited the country following the start of Moscow's conflict with Ukraine in 2022.

In August, Putin signed a decree allowing foreign investors to regain shares in Sakhalin-1.

Exxon took a $4.6 billion impairment charge on its 30% operator stake in the project off Russia's Pacific coast in April 2022.

Two sources familiar with the talks told Reuters in September that Exxon and Russian state-run energy giant Rosneft ROSN.MM had signed a non-binding initial agreement aimed at helping Exxon recoup its losses.

The agreement marked a tentative step towards repairing commercial ties, although little further progress is expected until a peace deal in Ukraine is reached and the United States and European Union ease sanctions on Russia.

Russia has said it would welcome the return of companies that pulled out of the country.

Alongside Exxon and Rosneft, India's ONGC Videsh ONVI.NS and Japan's SODECO were partner investors. The Russian government allowed both ONGC Videsh and SODECO to keep their stakes.

Earlier this month, three sources familiar with the matter said ONGC would pay into a Sakhalin-1 abandonment fund to retain its 20% stake in the project.

(Reporting by Marina Bobrova and Vladimir Soldatkin. Editing by Elaine Hardcastle and Mark Potter)

((vladimir.soldatkin@thomsonreuters.com; twitter: @vsoldatkin;))