KABUL, April 4 (Reuters) - The United Nations told some 3,300 Afghan staff not to come to work in Afghanistan for the next two days after the Taliban authorities signaled on Tuesday that they would enforce a ban on Afghan women working for the world body.

U.N. officials in Afghanistan "received word of an order by the de facto authorities that bans female national staff members of the United Nations from working," U.N. spokesperson Stephane Dujarric told reporters in New York.

The U.N. is looking into impacts and will meet with Afghan foreign ministry officials in Kabul on Wednesday to seek further clarity, he said. About 400 Afghan women work for the U.N.

Two U.N. sources told Reuters that concerns over enforcement had prompted the organization to ask all staff - male and female - not to come to work for 48 hours. Friday and Saturday are normally weekend days in Afghanistan, meaning U.N. staff would not return until Sunday at the earliest.

The U.N. mission in Afghanistan (UNAMA) earlier on Tuesday expressed concern that female staff in the eastern province of Nangarhar had been stopped from reporting to work.

"There was a much more official communication made in (Nangarhar provincial capital) Jalalabad. We were told through various conduits that this applied to the whole country," Dujarric, adding there was nothing writing.

"Female staff members are essential for the United Nations to deliver life-saving assistance," he said, adding that some 23 million people - more than half Afghanistan's population - need humanitarian aid.

The Taliban administration and the Afghan information ministry did not immediately respond to requests for comment.