Geir Lundestad writes in a book released on Thursday that the committee had expected the prize to deliver a boost to Obama. Instead the award was met with fierce criticism in the US, where many argued Obama had not been president long enough to have an impact worthy of the Nobel.
"Even many of Obama's supporters believed that the prize was a mistake," Lundestad wrote in excerpts of the book read by The Associated Press. "In that sense the committee didn't achieve what it had hoped for."
Lundestad, who stepped down last year after 25 years as the non-voting secretary of the secretive committee, noted that Obama was startled by the award and that his staff even investigated whether other winners had skipped the prize ceremony in Oslo.
That has happened only on rare occasions, such as when dissidents were held back by their governments.
"In the White House they quickly realized that they needed to travel to Oslo," Lundestad wrote.
Speaking to AP on Wednesday, Lundestad said he didn't disagree with the decision to award the president but the committee "thought it would strengthen Obama and it didn't have this effect."
It is rare for Nobel officials to discuss the proceedings of the secretive committee or publicly criticize each other. But in the book Lundestad also fired a parting shot at Thorbjorn Jagland who was the committee chairman for six years and is now a regular member.
Lundestad said that as a former Norwegian prime minister and sitting head of the Council of Europe human rights organization, Jagland should never have been appointed to the committee, which frequently emphasizes its independence.
Jagland declined to comment, said Daniel Holtgen, his spokesman at the Council of Europe.