(Cover) - EN Showbiz - Melissa Leo has become the first Academy Award winner to say f**k in an Oscar acceptance speech.

The actress won the best supporting actress award for her performance in The Fighter, beating off competition from Helena Bonham Carter (The Kings Speech), Hailee Steinfeld (True Grit), Jacki Weaver (The Animal Kingdom) and Amy Adams (The Fighter).

The 50-year-old actress - who was visibly overwhelmed by her win - put her hand over her mouth in horror after her outburst, after accepting her gong from legendary actor Kirk Douglas, 94.

When I watched Kate [Winslet] do this two years ago she made it look so f**king easy! she said when she collected her prestigious accolade.

The actress was embarrassed about her speech gaffe shortly after arriving backstage. She apologised for her use of offensive language.

Those words, I apologise to anyone that they offend. There is a great deal of the English language that is in my vernacular, she added.

The award was presented to the actress by screen legend Kirk Douglas who also made the moment dramatic. The actor did not open the envelope, teasing the audience with a series of tangents that began with "you know" .

After moments of hesitation, and finally declaring Melissa the winner, the actress arrived on stage, where she bowed before the three time lead actor nominee and asked what he was doing later in the evening.

The funny sequence of events became one of the evening's running jokes.

Justin Timberlake presented the award for animated short subject while mimicking Kirks behaviour, while Christian Bale - who won best supporting actor for The Fighter - said in his acceptance speech that he was not going to drop "an f-bomb" like his co-star.

Actresses including Tilda Swinton, Penlope Cruz and Cate Blanchett have previously won the title. (C) Cover Media