LONDON (AP) _ British drug companies Glaxo Wellcome PLC and SmithKline Beecham PLC said Monday that U.S. antitrust authorities have approved their merger, which will create the world's largest pharmaceutical company.

The U.S. Federal Trade Commission granted regulatory clearance for the $72 billion deal, the companies said in a joint statement. The merged company, which will be known as GlaxoSmithKline, must still be formally approved by the British High Court on Wednesday.

According to the companies, the U.S. authorities put no further conditions on the merger. Previously, SmithKline had agreed to sell the antiviral drugs Famvir and Denavir and anti-nausea drug Kytril to secure U.S. approval.

Earlier this year, U.S. authorities had requested additional information about the drug companies' products to help smokers quit. In the United States, Glaxo markets the prescription smoking-cessation product Zyban while SmithKline sells the over-the-counter products Nicorette and Nicoderm.

But while the Federal Trade Commission demanded no specific provisions regarding those products, it indicated that it will continue to review that area following completion of the merger, the companies said.

The merger had already won regulatory approval from the European Commission in May. It was endorsed by both companies' shareholders at meetings held on July 31, and is on schedule to be complete on Dec. 27.

Glaxo has its U.S. headquarters in Research Triangle Park, N.C. SmithKline's U.S. headquarters is in Philadelphia