Lawmakers want the new acting head of the Food and Drug Administration to allow sales of Barr Pharmaceuticals Inc's "morning-after" pill without a prescription, according to a letter made public on Tuesday.

Barr has pursued over-the-counter sales of its emergency contraceptive drug, called Plan B, for more than two years.

In August, the FDA announced an indefinite delay over the issue. Agency officials say the drug is safe and effective, but that they were unsure how to regulate a restriction based on age.

"We find it contradictory and disconcerting that the FDA's concerns are a direct result of the agency's own recommendations last May," the lawmakers, which included six Republicans and one Independent, wrote.