In a newly released image obtained by the Daily Mail, the actor, who rose to fame after starring as Sex Pistols' rocker Sid Vicious, is practically unrecognisable as the portly former British Prime Minister in biopic Darkest Hour.

The first look at Atonement director Joe Wright’s movie, which is already being mooted as an Oscar contender, shows the 58-year-old in full prosthetics, with the fuller face and balding pate of the late politician.

Dressed in a three-piece suit, bow tie and holding Churchill's ever-present cigar, Oldman is the image of the wartime leader who, within days of becoming Prime Minister, faced one of his most turbulent periods and defining trials as he was forced to galvanise the country, the King and his divided party to fight against Nazi Germany.

Oldman has only once been nominated for an Academy Award for his performance in 2011 movie Tinker Tailor Soldier Spy but he may have a strong chance again next season with this new biopic.

The film is set in May and June 1940, as the unstoppable Nazi forces roll across Western Europe and the threat of invasion is imminent.

Churchill must weather an unprepared public, a skeptical king, and his own party plotting against him, to withstand his darkest hour, rally a nation, and attempt to change the course of world history.

Kristin Scott Thomas plays his wife Clementine, Downton Abbey star Lily James stars as Churchill’s personal secretary, veteran actor John Hurt plays Churchill's predecessor Neville Chamberlain, and Australian Star Wars actor Ben Mendelsohn appears as King George VI.

Scripted by The Theory of Everything's Anthony MCCarten, the film from Working Title and Universal Pictures is due in cinemas in 2017.