WASHINGTON, Nov 7 (Reuters)(Correction) - A federal judge on Monday blocked a U.S. rule requiring tobacco companies to display graphic images on cigarette packs, such as a man exhaling cigarette smoke through a hole in his throat.

U.S. District Judge Richard Leon sided with tobacco companies and granted a temporary injunction, saying they would likely prevail in their lawsuit challenging U.S. health regulators' rule as unconstitutional because it compels speech in violation of the First Amendment.

In the first change in U.S. cigarette warning labels in 25 years, the Food and Drug Administration in June released nine new warnings to go into effect in September of 2012.

Covering the top half of the front and back of cigarette packs and 20 percent of printed advertisements, they must contain color graphics depicting the harmful health consequences of smoking, including diseased lungs, dead bodies and rotting teeth.

The FDA was instructed by Congress to issue the new regulations as part of 2009 legislation making the agency responsible for regulating tobacco products.

"The sheer size and display requirements for the graphic images are anything but narrowly tailored," Leon wrote in a 29-page opinion.

Just because Congress ordered the size and placement of the new warnings before charging the FDA with carrying out the mandate, "doing so does not enable this requirement to somehow automatically pass constitutional muster," he said.

The content of the images would also not likely survive constitutional muster because the FDA did not attempt to narrowly tailor those either, the judge said.

The tobacco industry had asked the court to block the FDA's new requirements, pending a final decision on their constitutionality. They argued they needed a quick ruling because they would have to start in November or December and spend millions of dollars to comply with the requirements.

Justice Department attorneys had argued that the money was a small fraction of the companies' net sales and so they would not suffer irreparable harm without the temporary injunction.

Reynolds American Inc's R.J. Reynolds unit, Lorillard Inc, Liggett Group LLC and Commonwealth Brands Inc, owned by Britain's Imperial Tobacco Group Plc sued the FDA in August over the graphic labels.

An FDA spokeswoman said the agency does not comment on proposed, pending or ongoing litigation. Representatives for Altria, Reynolds American and Lorillard could not immediately be reached for comment.

The case is R.J Reynolds Tobacco Co et al v. U.S. Food and Drug Administration et al, U.S. District Court for the District of Columbia, No. 11-cv-1482.

For R.J. Reynolds: Noel Francisco of Jones Day.

For Lorillard Tobacco Company: Floyd Abrams of Cahill Gordon & Reindel and Patrcia Barald of Covington & Burling.

For Commonwealth Brands: Phllip Perry of Latham & Watkins.

For Liggett Group: Jonathan Hacker of O'Melveny & Myers

For the FDA: William Schultz, Acting General Counsel of the FDA and Tony West, Assistant Attorney General.

(Reporting by Alina Selyukh and Jeremy Pelofsky; Additional reporting by Brad Dorfman)

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(An earlier version of this story misspelled the surname of Noel Francisco)

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