A British millionaire accused of trying to buy missile parts from undercover American agents and resell them to Iran pleaded guilty Thursday in a deal that would carry nearly three years in prison but could allow him to serve much of that time in his native United Kingdom.

Christopher Tappin, 66, a retired shipping magnate, had faced charges of conspiracy to illegally export defense articles, aiding and abetting the illegal export of defense articles and conspiracy to conduct illegal financial transactions.

He pleaded guilty to one count of the indictment Thursday at a hearing in El Paso, Texas. The deal calls for 33 months in prison, but as part of the agreement, prosecutors agreed not to oppose his request to be transferred back to his home country. He had faced up to 35 years in prison.

U.S. District Judge David Briones will decide Tappin's sentence Jan. 9. He has been living in an upscale Houston neighborhood since his release on a $1 million bond in April.

Federal prosecutors said Tappin, of the town of Orpington, southeastern England, and two other men sought to ship zinc/silver oxide batteries for Hawk Air Defense Missiles to Iran via the Netherlands.

Risked US national security

U.S. Attorney Robert Pitman said in a statement that “the defendant put at risk the national security of the United States and its allies by trying to sell to Iran the batteries that make the Hawk Missiles operational."

The federal indictment filed in 2007 said a cooperating defendant provided computer files showing Tappin was involved in the attempted battery deal and that he and the cooperating defendant had illegally sold U.S. technology to Iran in the past.

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The U.S. government alleged Tappin provided undercover agents with false documents to deceive authorities and circumvent the requirement for the batteries to be licensed by the government before being exported.

Tappin's extradition in February touched a nerve in Britain, where many contend the fast-track extradition arrangements between the United Kingdom and the United States are unfairly weighted in Washington's favor.

Iran's regular army has begun two days of ground and air military exercises. Iranian authorities say they want to increase combat readiness and deterrence against attack. NBC's Ali Arouzi reports.

But Tappin's attorney, Dan Cogdell, said Thursday that he didn't see much room for argument.

"He pled guilty because he was guilty," Cogdell said.

Tappin remained free on bond pending his sentencing. Cogdell said he expected Tappin to serve several months in a U.S. prison while authorities decided where to send him.

Western intelligence sees 'small signs of wavering' on Iran nuclear policy

Tappin fought extradition to the United States for two years until being denied a petition to take the case to Britain's Supreme Court. After he was brought to Texas, Tappin was held at the Otero County Jail for about two months, where he initially was put in solitary confinement at his request.

Two men have already been sentenced to prison for charges stemming from the indictment. Robert Gibson, another British national, pleaded guilty in April 2007 and was sentenced to 24 months in prison. Robert Caldwell, from Oregon, was found guilty in July of that year and received a 20-month sentence.

The Associated Press and Reuters contributed to this report.

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