Fancher, an occasional actor who subsequently wrote and directed The Minus Man, was actually working on Blade Runner before Scott, though the director eventually brought in screenwriter David Webb Peoples to substantially revise the screenplay. 

The press release officially announcing Fancher's involvement mentions that the duo initially conceived of their loose adaptation of Philip K. Dick's novel Do Androids Dream of Electric Sheep as the first in a series.  The overwhelmingly negative critical commercial reception of Blade Runner seemingly killed that notion.  Thirty years later, though, the availability of director's cuts and the passage of time have been exceedingly kind to the film, and they're getting their crack at another thematic meditation on humanity, artifice, and the future.

This news was perhaps inadvertently broken yesterday, when a Hollywood Reporter profile on Scott and Prometheus offhandedly mentioned that Fancher was working on the sequel.  It's official today, however.

For a time earlier this year, Alcon Entertainment producers Andrew Kosove and Broderick Johnson seemed confident that this new Blade Runner would be Scott's follow-up to Prometheus.  That won't be the case, though, as Scott is prepping The Counselor to start production in June.  That film is based on a screenplay by Pulitzer Prize-winning novelist Cormac McCarthy and will star Michael Fassbender, Javier Bardem, Cameron Diaz, and Brad Pitt.  If Prometheus is a success, Scott is apparently keen on directing a sequel to the Alien almost-a-prequel, so any more Blade Runner could be a long way off.

Here's the announcement:

LOS ANGELES, CA, MAY 16, 2012-Hampton Fancher is in talks to reunite with his "Blade Runner" director Ridley Scott to develop the idea for the original screenplay for the Alcon Entertainment, Scott Free, and Bud Yorkin produced follow up to the ground-breaking 1982 science fiction classic, it was announced by Alcon co-founders and co-Chief Executive Officers Broderick Johnson and Andrew Kosove.

The filmmakers are also revealing for the first time that the much-anticipated project is intended to be a sequel to the renowned original. The filmmakers would reveal only that the new story will take place some years after the first film concluded.

The three-time Oscar-nominated Scott and his "Blade Runner" collaborator Fancher originally conceived of their 1982 classic as the first in a series of films incorporating the themes and characters featured in Philip K. Dick's groundbreaking novel "Do Androids Dream of Electric Sheep?", from which "Blade Runner" was adapted. Circumstances, however, took Scott into other directions and the project never advanced.

Fancher, although a writer of fiction, was known primarily as an actor at the time Scott enlisted him to adapt the Dick novel for the screen. Fancher followed his "Blade Runner" success with the screenplays, "The Mighty Quinn" (1989) and "The Minus Man" (1999). He has continued to write fiction throughout his career.

Scott also will produce with Alcon co-founders and co-Chief Executive Officers Broderick Johnson and Andrew Kosove as well as Bud Yorkin and Cynthia Sikes Yorkin. Frank Giustra and Tim Gamble, CEO's of Thunderbird Films, will serve as executive producers.

The original film, which has been singled out as the greatest science-fiction film of all time by a majority of genre publications, was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant." The film was selected for preservation in the United States National Film Registry in 1993 and is frequently taught in university courses. In 2007, it was named the 2nd most visually influential film of all time by the Visual Effects Society.

State Kosove and Johnson: "It is a perfect opportunity to reunite Ridley with Hampton on this new project, one in fact inspired by their own personal collaboration, a classic of cinema if there ever was one."

Released by Warner Bros. almost 30 years ago, "Blade Runner" was adapted by Fancher and David Peoples from Philip K. Dick's groundbreaking novel "Do Androids Dream of Electric Sheep?" and directed by Scott following his landmark "Alien." The film was nominated for two Academy Awards (Best Visual Effects, and Best Art Direction). Following the filming of "Blade Runner," the first of Philip K. Dick's works to be adapted into a film, many other of Dick's works were likewise adapted, including "Total Recall," "A Scanner Darkly," "Minority Report," "Paycheck," and the recent "The Adjustment Bureau," among others.