Walt Disney has delayed and postponed the release of three major films, dealing a fresh blow to cinema operators struggling amid the pandemic.

The new Avatar and Star Wars films have been delayed by a year, while Mulan has been removed from schedules completely.

Mulan, already delayed because of cinema closures, had been scheduled for release at the end of August.

A rise in virus cases in the US and the impact globally on film production forced the change.

"It's become clear that nothing can be set in stone when it comes to how we release films during this global health crisis," a Disney spokesman said. "Today that means pausing our release plans for Mulan as we assess how we can most effectively bring this film to audiences around the world."

A rise in virus cases in the US and the impact globally on film production forced the change.

News that the release of three major Walt Disney films will be delayed or postponed is a fresh blow to cinema operators struggling amid the pandemic.

It had been hoped that Mulan might spark a late-summer rebound in cinema-going. The Avatar sequel is now set to debut in theatres in December 2022, and the next Star Wars movie in December 2023.

On Thursday, the AMC and Cineworld cinema chains pushed back the reopening date for their US outlets until at least mid-August, from the end of July.

New York City and Los Angeles, the two biggest markets in the US, have no concrete plans for reopening cinemas.

While cinemas in England were allowed to reopen from 4 July - as long as social distancing guidelines were followed - the picture across North America is much more uncertain.

In China, the world's second largest movie market, cinemas started to reopen this week after being closed for six months due to social distancing measures.

One film expert said the delay in Mulan was a "blessing in disguise" for Disney given the rising tensions between the US and China.

Chris Fenton is the author of Feeding the Dragon, a book about the power struggle between China and American business, particularly Hollywood film studios.

"No film based on Chinese mythology, set in China, and full of Chinese faces would perform well in America given the current state of anti-Chinese sentiment," Mr Fenton said.

"And in China, the same underperformance would be reciprocated due to hostility towards the US and American-made products, of which, Mulan is one."

The Mulan delay follows Warner Bros' decision to postpone the August release of Christopher Nolan's thriller Tenet. Cinema owners were pinning hopes on the two films to salvage part of the lucrative summer season.

Avatar 2 would have been one of next year's biggest films. It is the follow-up to James Cameron's 2009 blockbuster, which is the second highest-grossing film of all time.

Another delayed Disney film is Ridley Scott's historical thriller The Last Duel, which stars Ben Affleck and Matt Damon. That has been shifted from December of this year to October 2021.