Leonardo DiCaprio is tipped to receive another Oscar nomination for his performance as FBI director J Edgar Hoover in Clint Eastwood's biopic, J Edgar. The US actor talks to Shereen Low about collaborating with the legendary film-maker.

If there's one person who knows how Kate Winslet felt before she won an Academy Award, following her sixth nomination, it would be Leonardo DiCaprio.

After all, the 35-year-old who starred with Winslet in Titanic has yet to win one, despite a hat-trick of opportunities.

"I don't think anyone would say that they wouldn't want one. I think they would be lying," says DiCaprio, chuckling.

The heart-throb received his first nomination in 1993 for his break-through role in What's Eating Gilbert Grape, and then later for The Aviator and Blood Diamond.

DiCaprio's latest performance as John Edgar Hoover, the long-serving first head of the Federal Bureau of Investigation (FBI), in Clint Eastwood's J. Edgar, didn't land him a nomination this time, despite having been shortlisted for a Golden Globe.

The Los Angeles native prefers to bat away any awards talk.

"I have learned from my experiences in this industry that there is absolutely no way to control people's opinions on your performance in your movie," he says, leaning back in his chair.

"You go out there, promote your film and hope people like the work you did. But they're gonna respond the way they're gonna respond when they're in a room with that ballot."

Eastwood's biopic, which spans the five decades of Hoover's professional life, also stars Armie Hammer as Hoover's long-time confidante and associate director of the FBI, Clyde Tolson, and Dame Judi Dench as Hoover's domineering mother Annie.

The powerful leader, who headed the FBI through eight presidencies and three wars from 1935 until his death in 1972, is portrayed by DiCaprio during his glory years and through some less popular times.

"This was one of the most challenging characters I'd ever seen on the page, and it was terrific to breathe life into this person, because he was such a mystery," says DiCaprio.

"Hoover was incredibly ambitious as a young man. He was highly motivated to succeed in Washington, primarily due to his mother's expectations of him."

The actor has only praise for Dame Judi as his screen mum, describing himself as "a fan".

"She's a sweetheart, she couldn't be more lovely. But as soon as the cameras start rolling and you hear that voice, it's powerful," he recalls, laughing.

"We had a scene where I am freaked out, stuttering, and her voice just froze my spine. She has a way of commanding a scene in a room, and it's just astounding."

Transforming DiCaprio from Hoover in his mid-20s to his 77-year-old self took hairpieces, full facial prosthetics and padding.

"The ageing was difficult, that was a huge challenge," he admits. "It's a constant adrenaline rush every day - you have so much pressure and stuff to accomplish."

Little is known about the personal life of Hoover. And like his on-screen alter ego, DiCaprio, who previously dated models Gisele Bundchen and Bar Refaeli, keeps his love life under wraps.

The actor observes: "Early on in his career, capturing outlaws like John Dillinger helped Hoover to fashion the G-Man image in the eyes of the general public. There were comic books about them, they were on cereal boxes.

"From a character aspect, he was just a great grab bag of different eccentricities. You name it, this guy had it.

"We tried to give hints... from his obsession with cleanliness, to his stuttering, issues with his mother, questionable sexuality, the repressed lifestyle, obsession with communism, and ambition for personal glory."

Hoover's close relationship with Tolson - they were rumoured to be gay lovers - is explored in the biographical drama.

"They ate lunch and dinner together every day, went on vacations together. Whether they were together in any other respect... well, no one living knows the truth," says DiCaprio.

"In the film, it's seen as almost an unrequited love, but a lasting one, nonetheless."

In one scene, DiCaprio has to pucker up for a kiss with Hammer - quite a contrast after locking lips with beautiful women such as Marion Cotillard, Claire Danes and, of course, Winslet.

The actor's discomfort is clear as he gives a nervous laugh before saying: "These are the things we do as actors... I was in character."

According to DiCaprio, director Eastwood knew exactly what he wanted. "Clint was very clear, saying, 'I want you guys to beat each other up first, I want as much blood as possible, and I want you to grab each other as if you want to kill each other - and then that moment will happen'," he recalls.

"He was very adamant about the fact these men were of a certain time period and no matter what they felt it wasn't something they wanted to express. There was so much bottled up with their emotions for one another, it resulted in two men going fisticuffs first."

DiCaprio, who was named after the Italian Renaissance artist Leonardo da Vinci, admits awards aren't the be-all and end-all of his career.

"I don't think I ever expected anything like an Oscar ever, to tell you the truth. That is not my motivation when I do these roles," he insists.

"I really am motivated by being able to work with great people and create a body of work that I can look back and be proud of.

"I grew up when I was 15 when I had my first opportunity in movies. I watched every great movie for a year and a half, and since then I've asked myself how I can emulate such artistry. That's really my motivation. I want to do something as good as my heroes have done."

With upcoming roles in Baz Luhrmann's The Great Gatsby and Quentin Tarantino's Django Unchained, DiCaprio plans to make the most of his time in the spotlight.

"I just really love doing what I do. I know every career is fleeting and there will be time periods when I don't get the opportunities that I'm getting right now, so I am taking advantage of them."

For local screenings of J. Edgar, click here.