It was the film that established Gwyneth Paltrow as a Hollywood star - but her Oscar-winning role in 'Shakespeare in Love' almost didn't come to pass, according to its producer.

A new essay penned by producer Ed Zwick has revealed some seriously juicy gossip around the original Universal Studios production of the film in 1991 - most notably surrounding Julia Roberts and her diva-esque demands, fresh from the success of 'Pretty Woman'.

In the essay, Zwick said that Roberts - who was originally cast in the role of Viola DeLesseps - had her heart set on acting opposite Daniel Day-Lewis as the male lead of Shakespeare, even though he had committed to shooting 'In the Name of the Father' with Jim Sheridan at the time.

He said that Roberts encouraged him to cast Day-Lewis, saying "He’s brilliant - he’s handsome and intense. And so funny! Did you see his performance in ‘A Room with a View?’ He’s done Shakespeare, too. Don’t you think he’d be perfect?…I can get him to do it."

She reportedly had her assistant send Day-Lewis two dozen roses with a card that read "Be my Romeo".

When it eventually became apparent that despite her best efforts, Day-Lewis was remaining committed to 'In the Name of the Father', the 'Shakespeare in Love' producers had Roberts participate in 'chemistry reads' with other actors to see how well they worked together. One of them was Ralph Fiennes.

"Even as Ralph did his best to elicit the famous smile, Julia barely acknowledged him," Zwick recalled. "I’m not suggesting she was deliberately sabotaging, but it was a disaster nonetheless. I tried to catch Ralph’s eye to apologize as he left but he couldn’t get out of there fast enough. After he was gone, I turned to Julia, awaiting her reaction. ‘He isn’t funny’ is all she said."

He added: "The rest of that day and every day of the week that followed went just as badly. I no longer have my cast lists, but among the yet-to-be-discovered young actors, I remember: Hugh Grant, Rupert Graves, Colin Firth, Sean Bean, Jeremy Northam. Julia found fault with all of them: one was stiff, another wasn’t romantic, and so on."

When she eventually agreed to test opposite Paul McGann, disaster awaited. "On the morning of the test, Julia emerged from makeup, looking radiant in full period costume," wrote Zwick. "But once she began to say the words, something was wrong. There was no magic. The problem wasn’t the script. Or Paul McGann. It was Julia. From the moment she began to speak it was clear she hadn’t been working on the accent."

The next day, Roberts flew back to the US and abandoned the project - but not before costing Universal an estimated $6 million.

Zwick said that she had not spoken to Roberts since, but has "observed from afar as her work grew in depth and stature. I bear her no ill will. She was a frightened 24-year-old. I wasn’t much older, trying to act the grown-up as I watched the Globe Theatre torn down. And with it my dreams of grandeur."

Harvey Weinstein's Miramax would go on to revive 'Shakespeare in Love' with Paltrow and Joseph Fiennes, which was released in 1998 and went on to bag seven Oscars.