London, England (CNN) -- Wednesday's release of a British computer expert held by Shiite Muslim insurgents in Iraq since 2007 came about as part of efforts to settle the six-year-old insurgency, an Iraqi government spokesman said.

Peter Moore had been held hostage since May 2007. He was released Wednesday in good health, British Foreign Secretary David Miliband told reporters in London, England.

"He is undergoing medical checks and he will be reunited with his family as soon as possible back in the UK," Miliband said. "He is obviously -- to put it mildly -- delighted at his release."

A little known-group calling itself The Islamic Shiite Resistance of Iraq claimed to have been behind Moore's kidnapping. Iraqi government spokesman Ali al-Dabbagh said government officials were not involved in the talks that led to Moore's release, but said the decision to free him "is part of the national reconciliation program" aimed at convincing Iraq's remaining armed factions to lay down their arms.

"The Iraqi government was not part of this effort, but was always supportive of the efforts," al-Dabbagh said. He said the goal is to convince those factions still taking up arms against the U.S.-backed Iraqi government to "give up all violence and to be part of the political process through the normal rule of law here in Iraq."

Moore, a computer expert for U.S.-based consulting firm BearingPoint, was kidnapped amid the sectarian warfare and insurgent attacks that ravaged Iraq in the years following the U.S. invasion in 2003. He was one of five Britons seized from the Iraqi finance ministry by people posing as security forces and government workers on official business. The other four men were guards working for the Canadian security firm GardaWorld.

The bodies of security guards Jason Creswell and Jason Swindlehurst were handed over in June 2007, while Alec MacLachlan's body was returned in September 2009. The fourth, Alan McMenemy, is believed dead, though there was no indication Wednesday of his status.

"We have believed for some time that he has been killed and his immediate family have been told our view of his likely fate," Miliband said. "I call again today on the hostage-takers to return Alan's body as soon as possible."

Speaking to CNN from his home in the English city of Leicester, Moore's father, Graeme Moore, said he was "absolutely overjoyed for the lad." But he sharply criticized the British Foreign and Commonwealth Office and Miliband, whom he said kept them in the dark about his son's case.

The elder Moore said he heard from a reporter that the Foreign Office planned to release a statement on his son's case, "and I did suspect the worst."

"But when I saw the breaking news on the television, I went through the ceiling with joy," he said.

He called Miliband's statement that the agency had been in "close touch" with the Moore family a "disgraceful" lie, telling CNN, "They don't talk to Peter's family. They never have."

There was no immediate response from the Foreign Office to the criticism.

Moore's kidnappers released at least three videos. In December 2007, the Arabic language TV station Al-Arabiya showed a video of a man who identified himself as "Jason." He said on tape that the date was November 18. The hostage-takers demanded in the video that all British troops be withdrawn from Iraq within 10 days or they would "kill the hostage ... as an initial warning."

In February 2008, Moore appeared in a video, pleading with the British government to agree to a prisoner swap.

"It's a simple exchange -- release those that they want so we can go home," he said. "It's as simple as that. It is a simple exchange of people. This is all they want, just have their people released."

The British Embassy in Iraq received a third video in March, but it has not disclosed its contents.

The United States, too, is awaiting the release of almost a dozen Americans listed as missing in Iraq, some for as many as six years, U.S. State Department spokesman Darby Holladay said in an e-mail to CNN. While the U.S. government has called for their release and information on their status, Holladay said, the government's policy is to not make concessions to terrorists or hostage-takers, including concessions such as prisoner release or ransom.

CNN's Mohammed Tawfeeq and Jill Dougherty contributed to this report.