NEW YORK (CNNMoney) -- Wal-Mart said Friday it will carry the Plan B emergency contraceptive pill for over-the-counter sale possibly by the end of the year.

In a statement e-mailed to CNNMoney.com, Wal-Mart spokesman Kevin Gardner said the company will sell Plan B to women 18 and over once the new packaging has been approved by the Food and Drug Administration (FDA).

The Plan B pill, which can prevent pregnancy if taken within 72 hours after intercourse, has been sold as a prescription drug since 1999. On Thursday, the FDA approved over-the-counter sale of the pill.

Gardner said Plan B will be kept behind the counter and that the company will require an I.D. from consumers over the age of 18 who want to buy the product.

Consumers 17 and under will be able to buy Plan B only by prescription, Gardner said.

Wal-Mart (Charts), the world's No. 1 retailer, began stocking Plan B contraceptives - commonly referred to as the "morning-after pill" - at all of its pharmacies on March 20 this year.

Other drugstore operators were also mulling selling Plan B.

Controversy has surrounded the drug since its development. Pro-life activists are against Plan B since they believe that the emergency contraception is equivalent to abortion.

Mike DeAngelis, spokesman for CVS (Charts), the No. 2 drugstore chain behind Walgreen (Charts), said the company would not take any actions until it had reviewed the FDA's formal ruling on the matter.

"Once the FDA has made its review on Plan B available to us, we will review it and then work with the manufacturer to understand the new regulatory requirements surrounding the sales of Plan B without a prescription," DeAngelis said. DeAngelis also said new packaging would be needed, and that this would not be available from the manufacturer until the end of this year.

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