President Obama’s trade representative has vetoed a ban on imports of some Apple iPads and older iPhones, reversing a ruling in favor of rival Samsung Electronics.

U.S. Trade Representative Michael Froman today overruled a June decision by the U.S. International Trade Commission. The commission banned imports of the iPhone 4 and some variants of the iPad 2 when it ruled that the Chinese-made Apple devices violate a patent held by Samsung.

But Froman says in a letter to the commission that he has concerns about patent holders getting too much leverage over competitors that use their technology under licenses.

Samsung and Apple are in a global legal battle over smartphones. Apple argues Samsung’s Android phones copy vital iPhone features. Samsung is fighting back with its own complaints.