Key moments in the Battle of Bakhmut in Ukraine's east

KYIV, (Reuters) - The battle for the small city of Bakhmut in Ukraine's eastern Donbas region has become the longest and bloodiest of Russia's full-scale invasion of Ukraine.

Here is a timeline of key events there:

May 8, 2022 - Ukraine confirms its forces have withdrawn from Popasna, a town around 15 miles (24 km) east of Bakhmut, with a major road running between the two settlements. Russian forces can now advance towards Bakhmut and pound it with artillery.

Aug. 9, 2022 - British defence intelligence says the Bakhmut axis has been Russia's most successful front over the last 30 days and troops have advanced about 10 km (6 miles) in the region.

Oct. 8, 2022 - The date pinpointed by Russian mercenary leader Yevgeny Prigozhin as the start of the assault on Bakhmut city by his Wagner fighters.

Oct. 15, 2022 - Ukrainian President Volodymyr Zelenskiy says the situation in Bakhmut is "the most difficult" of all the front lines. "We are holding our positions," he says.

Dec. 20, 2022 - Zelenskiy pays a surprise visit to the city, where he hails his "superhuman" troops and urges them to fight on.

Jan. 25, 2023 - Ukraine's military says it has withdrawn from the town of Soledar, north of Bakhmut. Two weeks earlier, Prigozhin posted a photo of him and his fighters in what he said was one of Soledar's salt mines.

Feb. 3, 2023 - Zelenskiy says Ukraine will fight "as long as we can" for Bakhmut. "Nobody will give away Bakhmut ... We consider Bakhmut our fortress," he says.

March 22, 2023 - Zelenskiy makes a surprise visit to troops near Bakhmut to thank them for their bravery and hand out awards.

April 2, 2023 - Prigozhin hoists a Russian flag by what he says is the Bakhmut city hall. He says taking the building means Bakhmut has been captured by Moscow "from a legal point of view". Ukraine rejects his claim, saying it is not clear where Prigozhin raised the flag.

April 11, 2023 - Prigozhin says Wagner control more than 80% of Bakhmut. Ukraine denies this, saying it controls "considerably" more than 20% of the city.

April 26, 2023 - Britain's Ministry of Defence says fighting has reached Bakhmut's western outskirts over the past week, especially around the settlement of Khromove on its northwestern edge, as Ukraine seeks to retain control of the main access road.

May 1, 2023 - Ukraine claims to have ousted Russian forces from some positions in Bakhmut amid fierce battles.

May 10, 2023 - Ukraine's ground forces commander says Russian units in some parts of Bakhmut have retreated by up to 2 km (1.2 miles).

May 19, 2023 - Ukraine says it has repelled attacks by Russian forces trying to recapture ground around Bakhmut. Prigozhin says "heavy, bloody battles" are continuing and his men are close to completely capturing Bakhmut.

May 20, 2023 - Prigozhin says Wagner have completed the capture of Bakhmut. Ukraine says the situation there is critical, with its troops still defending the southwestern part of the city.

(Reporting by Max Hunder; Editing by Angus MacSwan, Peter Graff and Giles Elgood)