Image copyright Getty Images Image caption Trainspotting's sequel was filmed in Edinburgh in 2016

Oscar-winning director Danny Boyle has ruled out a third instalment of the Trainspotting films "at the moment".

The original 1996 movie, based on Edinburgh author Irvine Welsh's novel, was followed up by a sequel in 2017.

At the Scottish premiere of his new movie Yesterday, Boyle said he was not thinking of reuniting Renton, Begbie and Spud for a third film.

He told BBC Scotland's The Nine there would need to be a good reason to return to the characters again.

The 2017 sequel came more than 20 years after the original black comedy drama about a group of heroin addicts in Edinburgh became a huge hit.

Image copyright Mirrorpix/Getty Images Image caption The first Trainspotting movie was released in 1996

Its stars Ewan McGregor, Robert Carlyle, Ewen Bremner and Jonny Lee Miller were reunited for a film that looked at what had happened to them in the intervening decades.

Boyle said he did not want to make a third film which would be "just treading water".

"You need to make it about something and obviously in the case of the second one it was about their ages - what had happened to them in their lives or not happened to them."

Asked if he thought the Trainspotting films had gone as far as they could he said: "At the moment."

Image copyright Getty Images Image caption Boyle (left) has suggested there should be spin-off movies for Irvine Welsh's characters

Boyle has previously suggested it would be an idea to have "solo" spin-off Trainspotting films based on characters such as Begbie, who Welsh wrote about in the novel The Blade Artist.

However, the director did not say he was planning to make the movies.

The 62-year-old director, who won an Oscar for Slumdog Millionaire, made his feature film debut in 1994 with Shallow Grave, which was set in Edinburgh.

Image copyright PA Image caption Danny Boyle was in Edinburgh for the premiere of his new film Yesterday

He followed this up with Trainspotting, which was also set in the Scottish capital.

Appearing at the Edinburgh International Film Festival, Boyle said: "It is nice to be back and I am very indebted to the city, for my career and for some of the glorious times we had here.

"I'd certainly return. I'm not quite sure for what film yet but if there was ever a chance of filming here again I wouldn't hesitate."

Boyle's new film Yesterday is a comedy about a man who wakes up after an accident caused by a global power outage to a world that has forgotten all about The Beatles.