A ban on sales of older models of Apple's iPad and iPhone in the US has been overturned by the Obama administration.
In June, the US International Trade Commission (ITC) ruled that Apple infringed a patent of rival Samsung.
President Barack Obama's trade representative has now vetoed that decision because of its "effect on competitive conditions in the US economy".
Such a veto is a relatively rare event.
The patent related to 3G wireless technology and the ability to transmit multiple services correctly and at the same time. The ITC ordered a halt on all imports and sales on AT&T-sold models of the iPhone 4, iPhone 3, iPhone 3GS as well as the iPad 3G and iPad 2 3G. Some of those devices are no longer on sale in the US.
Such patents are called "standard essential patents" and they cover technology that must be used to comply with standards set by the industry as a whole.
