Two senior Democratic lawmakers called for an end Tuesday to the force-feeding of dozens of Guantanamo detainees, clashing with the White House which argued that they "don't want these individuals to die."

Number two Senate Democrat Dick Durbin said he and Senate Intelligence Committee chair Dianne Feinstein, who has long called for the closure of the detention facility, will write President Barack Obama asking him to "exercise his executive authority" and end the force-feeding.

"I believe Congress has been complicit in the current, complicated situation," Durbin said in a Senate Judiciary Committee hearing on Obama nominee James Comey to head the FBI.

Of the 166 inmates at the US Navy detention center in southeastern Cuba, 106 have gone on hunger strike. Of those, 45 of them are being force-fed.

Feinstein, who visited Guantanamo earlier this year and was briefed on the forced feeding, provided graphic details of the process.

"Detainees are restrained in a chair by body, by foot, by hand, and twice a day a tube is inserted -- perhaps covered with olive oil -- up the nose and down into the stomach," Feinstein said.

"This goes on week after week, and month after month."

Several detainees are no longer considered a threat to the United States and have been cleared for transfer, including the petitioner in the latest legal case, Jihad Dhiab.

But they remain in limbo, and some have gone on hunger strike as "an expression of acute hopelessness," Feinstein said.

"Many of (them) are being force-fed to keep them alive," she added. "In my view, this is inhumane."

A day earlier, US District Court Judge Gladys Kessler ruled against Dhiab's bid to have his force-feeding blocked, citing existing law which prevents intervention in aspects of detention at Guantanamo.

But Kessler described the force-feeding of detainees as "a painful, humiliating and degrading process," and said Obama was the one person who could "directly address the issue."

Asked about the judge's unusual move, the White House defended the controversial policy.

"We don't want these individuals to die," Obama's spokesman Jay Carney said Tuesday. "The action being taken is to prevent that from happening."