Movies
The sixth instalment in the franchise was scheduled to hit cinemas on November 21, but fans will now have to wait until July 2009, says The Hollywood Reporter.
Warner Bros. president Alan Horn put the delay down to the recent writers' strike in the US.
He said in a statement: "Like every other studio, we are still feeling the repercussions of the writers' strike, which impacted the readiness of scripts for other films - changing the competitive landscape for 2009 and offering new windows of opportunity that we wanted to take advantage of.
"We agreed the best strategy was to move Half-Blood Prince to July, where it perfectly fills the gap for a major tentpole release for midsummer."
The studio still intends to make a two-film adaptation of series finale Harry Potter And The Deathly Hallows, the first of which will open on November 19, 2010.
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