Game of Thrones fans caused a lot of uproar on social media after it was confirmed that the series' season 8 and final season will not air until 2019.

But HBO president Casey Bloys has defended the date. Bloys told TV Line: "It wasn't necessarily a delay," adding that the 2019 announcement came after showrunners David Benioff and D B Weiss took over the season 8 helm. "It was based on when they felt that they could deliver a show that they are most proud of."

He added: "I suppose we could've said to them, 'You must deliver by this date.' But we've worked with them a long time and I trust them to tell us, 'This is the time we need to make it good.' So I don't know that it's a delay as much as it is 'This is the time required to deliver at the level that they think the fans expect.'"

Bloys also shared an update on the Game Of Thrones spinoff series, and said the earliest it would air would be one year after Game of Thrones' series finale, around 2020.

He told TV Line that there are some things that are "potentially very exciting". He added: "Should we go forward and make a pilot and [then] a series, nothing would air on HBO until at least a year after Game of Thrones ends. We want the final season of Game of Thrones, being the special event that it is [to stand on its own]. We don't want to use it to launch [a new series]. We want some separation there."

In 2017, HBO announced deals with four writers — Carly Wray, Jane Goldman, Brian Helgeland and Max Borenstein – for a spinoff series. This, according to Bloys, is set to "explore different time periods of [George R R Martin]'s vast and rich universe. There is no set timetable for these projects. We'll take as much or as little time as the writers need and, as with all our development, we will evaluate what we have when the scripts are in."