With just days to go until a Monday deadline, New York Times Executive Editor Bill Keller yesterday confirmed that he was unlikely to get 100 newsroom volunteers to accept buyouts — meaning he’ll wield the layoff ax for the second time in two years.

Sources said the newsroom was in a state of high anxiety this week because of chatter that just 50 unionized editorial workers from the Newspaper Guild are expected to step forward for voluntary buyouts by the deadline of close of business Monday.

“We will not know until then exactly how many Guild and excluded employees have opted to take buyouts, but it is almost certain the number will fall short of the 100 we need,” Keller said in a memo to staff yesterday. “If that is indeed the case, as we expect, we will be forced to resort to some number of layoffs.”

Keller said in the memo that he would meet with Guild members next week to identify those getting cut, and then inform those employees the following week. Keller has said the cuts must be made before year-end.

“How about some of the masthead taking a bullet for the sake of the staff,” suggested one insider who hopes to survive.

Indeed, Times management can volunteer for a buyout, though sources said that package isn’t nearly as generous as the one offered to Guild members, which guarantees pay of up to two years for longtime employees.

As The Post reported yesterday, longtime business reporter Geraldine Fabrikant is among those expected to take a buyout. In addition, Alex Berenson, who is about to publish his fourth espionage thriller “The Midnight House” in February, and is believed to command mid- to high-six-figure advances for each new book, is also considering taking a buyout.

“I am likely leaving, though I haven’t signed anything yet,” he said. “I’m now writing one novel a year, and that doesn’t leave a lot of time for the paper. Basically, my night job turned into my day job when I wasn’t looking.”

Jonathan Glater, who covers law for the Times, is also taking the buyout. A message on his Times voicemail said his last day will be Dec. 9.

The Washington bureau will lose at least four veteran reporters, sources said, including Neil Lewis, David Johnston, David Stout and Stephen Labaton. Metro section reporter Ralph Blumenthal and business reporter Louis Uchitelle are also expected to leave the paper.