Disney fans will have to wait a little longer for some of the top blockbusters after the company announced a reshuffle of its release calendar.

On the list are many of its eagerly awaited instalments of Marvel, Star Wars, and Avatar movies, US media report.

Avatar producer Jon Landau wrote on Twitter that the filmmakers needed more time to complete the next movies.

Disney has not given a reason for the delays.

The move comes amid the ongoing strike by Hollywood writers, which some believe is causing production shutdowns that could have an impact on release timelines.

"Movies like this can't be made without scripts (despite what some critics might say), and with writers not currently working on them, things have to be delayed," according to media website Gizmodo.

The most significant push in the calendar, announced on Tuesday, is the release of Avatar movies, a science-fiction series set on the fictional moon of Pandora. Avatar 3 will now be out a year later on December 19, 2025. Avatar 4 moves several years to December 21, 2029, and Avatar 5 moves to December 2031.

Director James Cameron, who launched the first "Avatar" in 2009, has said he may not direct the fourth and fifth instalments, the Associated Press reported. By December 2031, the 68-year-old Cameron would be 77.

"Each Avatar film is an exciting but epic undertaking that takes time to bring to the quality level we as filmmakers strive for and audiences have come to expect,"Avatar producer Jon Landau wrote on Twitter.

The other significant push in the calendar is for the Star Wars films. Two films in the series are now planned for 2026 - one was pushed from December 2025 to May 2026, another was added for December 2026. The studio hasn't released a Star Wars film since 2019.

A reshuffle was also announced for the bulk of Marvel series - most notably Avengers: Kang Dynasty is being pushed from May 2025 to May 2026.

Other changes in Marvel releases include most films being delayed a few months. "Captain America: Brave New World" will open in July 2024 instead of May 2024, after which comes "Thunderbolts" in December 2024, "Blade" in February 2025 and "Fantastic Four" in May 2025.