MONDAY 6:15 PM: TOLDJA! Marvel Studios has just confirmed Tom Hiddleston as Loki.

EXCLUSIVE MONDAY UPDATE: I’ve learned that Marvel Studios president Kevin Feige and Thor director Kenneth Branagh have cast their Loki, the nemesis to the lead in Thor set for release on May 20, 2011. He’s Tom Hiddleston, unknown to American audiences but an award-winning British actor and Royal Academy Of Dramatic Arts (RADA) graduate. He played Winston Churchill’s son in HBO’s The Gathering Storm, but, more to the point, note that Hiddleston starred in Ivanov opposite Sir Kenneth on the London stage and also starred with him in the BBC miniseries Wallander. In 2008, Hiddleston was nominated twice for the Laurence Olivier Stage Award for Best Newcomer – for his roles in Othello and Cymbeline. He won for the latter.

Marvel Studios won’t confirm my news, but Hiddleston had been considered as a possible Thor. See my previous, ‘Thor’: Unknowns? There had been a big Internet push to cast Josh Hartnett in the Loki role but instead Marvel went with an unknown. This follows my news of the weekend casting of 25-year-old Aussie actor Chris Hemsworth as Thor since Branagh was in town to finalize the principal cast. See my previous, EXCLUSIVE: Chris Hemsworth Is ‘Thor’.

I hear the Marvel Studios press release about both castings is being written and should be released soon. Chris Hemsworth also a virtual unknown to American audiences, yet he was approved to play the lead role in Thor by Marvel Studios president Kevin Feige and the film’s director Kenneth Branagh. Hemsworth can currently be seen as “George Kirk” in J.J. Abrams’ Star Trek reboot and also just snagged the lead in Red Dawn for United Artists last Thursday. (He’s currently filming Joss Whedon’s horror flick Cabin In The Woods for UA, and I heard the studio was so hot on him that’s why it cast Hemsworth in the action pic.) The 25-year-old hunk played “Kim Hyde” on 171 episodes of Home and Away, the successful Oz TV series where Heath Ledger started. The way Chris Hemsworth got the part of Thor is one of those great Hollywood stories that happens only once in a blue moon. I have all the details here.