(Updates throughout with intelligence official comments, details, quotes)

WASHINGTON, May 9 (Reuters) - Venezuelan President Hugo Chavez's ties to Colombian rebels are deeper than previously thought, a U.S. intelligence official said on Friday following an analysis of files on a dead guerrilla leader's laptops.

The files appear to be authentic and underscore U.S. concerns about Chavez's quest for more influence in the region, the official said. Their discovery in March raised speculation the United States would put Venezuela on its list of state sponsors of terrorism.

"It (the analysis) reinforces the U.S. government's strong position that Chavez is attempting in various ways to project his influence throughout the region and that influence in some ways could be construed as destabilizing," the intelligence official said.

Chavez contends the Colombian government faked the files.

Although Chavez's sympathies for the leftist Revolutionary Armed Forces of Colombia are well known, Colombia has said the files seized in a March attack show Chavez offered financial support to the group.

The Wall Street Journal reported on Friday that the files also indicate Venezuela offered to arm the rebel group, which is known as FARC, possibly with rocket-propelled grenades and ground-to-air missiles. It said Venezuela offered FARC the use of a port to receive arms shipments.

The intelligence official told Reuters "the documents provided by the Colombian government appear to be authentic."

The files document discussions between the rebels and Chavez about closer ties and portray a "deeper relationship than previously known," the official said.

The March attack by Colombia on a rebel camp in Ecuador killed a senior FARC leader and inflamed regional tensions. That and other recent attacks are seen as having weakened the rebel group that has been fighting a four-decade civil war in Colombia, to the point where FARC is "on its heels," the intelligence official said.

"However, they have shown an ability in the past to regroup and to regenerate leadership."

Bernardo Alvarez, Venezuela's ambassador to the United States, told the Journal in an interview on Wednesday, that the computer files were "false and an attempt to discredit the Venezuelan government."

The files indicate Venezuela has raised the prospect of drawing up a joint security plan with FARC and has sought basic training in guerrilla-warfare techniques, the Journal said, suggesting Chavez was preparing for a possible U.S. invasion of Venezuela.

(Reporting and writing by Randall Mikkelsen at Guantanamo Bay U.S. Naval Base, Cuba; Editing by Bill Trott)

AlertNet news is provided by