MOSCOW, July 4 (Reuters) - Russia's only aircraft carrier, the Admiral Kuznetsov, which has suffered a series of repair delays, may re-enter service by the end of next year, the country's TASS state news agency reported on Tuesday.

The ship, launched in 1985, had been due to undergo a refit that would have seen it operational in 2023.

"According to the adjusted plan, factory sea trials of the aircraft carrier should begin in the spring of 2024," TASS reported, citing an unnamed defence source.

"If the tests pass without glitches, then the ship can be handed over to the fleet at the end of 2024. If something goes wrong during the tests, then a shift to 2025 is inevitable."

In December 2019, at least one military serviceman was killed and 12 people were injured by a fire on board the ship. The previous year it sustained damage during repair work when the floating dock holding it sank and a crane crashed onto its deck.

The carrier gained notoriety in Britain in 2017 when then-Defence Secretary Michael Fallon dubbed it the "ship of shame" as it passed through waters close to the English coast belching black smoke.