Cate Blanchett has won the Bafta for best actress for her role in Woody Allen's Blue Jasmine, beating the likes of Judi Dench and Sandra Bullock.

Blanchett began her acceptance speech by saying: "I was sitting in row G, so I thought that was a sign I wouldn't be getting up." She added: "God I'm unfit!"

The Australian actor dedicated her speech to Philip Seymour Hoffman, who died on 2 February, calling him a "monumental presence" and celebrating "your monumental talent, your generosity and your unflinching quest for truth not just in art but in life".

"You raised the bar continually," Blanchett continued. "Phil, buddy, this is for you, you bastard, I hope you're proud."

In Blue Jasmine, she plays a former socialite suffering mental collapse following a separation from her rich financier husband. She is also Oscar-nominated for the role, and is the favourite to win.

Talking to the Guardian, she described the "sense of fated collapse" to Jasmine, a woman in a world where "the constructed sense of selves is often very much more real that what is actually going on".

The win comes amid a tense time for her director. Blanchett was recently addressed directly by Dylan Farrow, Woody Allen's adopted daughter, following Farrow's accusations that Allen had sexually assaulted her. Wrote Farrow in an open letter: "What if it had been your child?"

"It's obviously been a long and painful situation for the family and I hope they find some sort of resolution and peace," Blanchett has said.

• The winners as they are announced
• Xan Brooks is live-blogging the ceremony here