Samsung Electronics has scored a victory over rival Apple in their long-running dispute over mobile device patents after a US trade agency issued an order banning older but still-popular Apple products from the US market.

The US International Trade Commission (ITC) ruled on Tuesday that the Silicon Valley company had infringed on a patent owned by Samsung that involves the ability of devices to transmit multiple services simultaneously and correctly through 3G wireless technology.

The independent federal agency slapped a ban on the import or sale of the iPhone 4, iPhone 3GS, iPad 3G and iPad 2 3G distributed by AT&T, the biggest seller of Apple devices in the United States when Samsung filed its complaint in 2011.

We believe the ITC’s Final Determination has confirmed Apple’s history of free-riding on Samsung’s technological innovations. Statement from Samsung,

The products are assembled in Asia. US President Barack Obama has 60 days to review the ruling. If he does not veto the order, it will go into effect.

It is not immediately clear what the impact could be on Apple or AT&T should Obama let the ruling stand, since the decision remains subject to a potentially prolonged appeals process.

While the products targeted are more than a year old, some models such as the iPhone 4 remain solid sellers.

The most recent version covered by the ITC's decision - the iPhone 4 - is now given away with a contract offered by carriers including Verizon Wireless, which is not affected by the ruling.

"We are disappointed that the commission has overturned an earlier ruling and we plan to appeal. Today's decision has no impact on the availability of Apple products in the United States," Apple spokeswoman Kristin Huguet said in a statement.

'History of free-riding'

In response to the verdict, Samsung said, "We believe the ITC's Final Determination has confirmed Apple's history of free-riding on Samsung's technological innovations".

The iPhone 4 could be phased out within a year should Apple stick to schedule and release a new version of the iPhone 5 in the fall as many in the industry expect.

Still, if the import ban goes into effect, US customs agencies enforcing the ban could well end up delaying other Apple products, according to Susan Kohn Ross, a partner in the Los Angeles office of Mitchell Silberberg & Knupp.

"This is going to create a huge distortion for Apple," she said. "Customs has a very difficult job now. They have to look at every shipment."

The iPhone accounts for about half of Apple's revenue.

While the company does not disclose sales data on individual smartphones and tablet models, the most current version of the iPhone typically accounts for the biggest chunk of iPhone shipments of more than 100 million units annually.