The White House "kill list"--a regularly updated chart showing the world's most wanted terrorists used by President Barack Obama during kill or capture debates--may soon be getting a rule book to go with it.

According to the New York Times, the administration--faced with the possibility that President Obama might lose the 2012 election to Mitt Romney--"accelerated work in the weeks before the election to develop explicit rules for the targeted killing of terrorists by unmanned drones, so that a new president would inherit clear standards and procedures."

Until now, President Obama has had the "final moral calculation" overseeing the "kill list," the existence of which was first revealed in May in the wake of a drone strike that killed an al-Qaida leader.

But according to the paper, administration officials are looking to curb the power of the commander in chief with the rule book:

"There was concern that the levers might no longer be in our hands," said one official, speaking on condition of anonymity. With a continuing debate about the proper limits of drone strikes, Mr. Obama did not want to leave an "amorphous" program to his successor, the official said. The effort, which would have been rushed to completion by January had Mr. Romney won, will now be finished at a more leisurely pace, the official said.

President Obama has voiced his support for such rules.

"Creating a legal structure, processes, with oversight checks on how we use unmanned weapons is going to be a challenge for me and my successors for some time to come," President Obama said in an interview with author Mark Bowden for "The Finish," a book on the killing of Osama bin Laden. "There's a remoteness to it that makes it tempting to think that somehow we can, without any mess on our hands, solve vexing security problems."

[Also read: 'Secret kill list' shows president is final word on terrorist killing missions]

The U.S. drone program, which was launched by President George W. Bush, has been expanded under the current administration. Since Obama took office in 2009, there have been more 300 drone strikes carried out by the U.S. military, according to the Times.

Earlier this year, critics of the "kill list" launched a petition on the White House website to create a "Do Not Kill" list to protect U.S. citizens from drone strikes by their own government. The petition, though, failed to meet the 25,000-signature threshold required to get an official response from the White House.