Apple will probably launch the iPhone 5 on Wednesday (Sept. 12), but Samsung is looking to spoil the party. The Korean smartphone maker recently lost the long-running Samsung-Apple patent trial, and it is now suing Apple over the use of 4G LTE in the iPhone 5.

"It's true that Samsung Electronics has decided to take immediate legal action against the Cupertino-based Apple. Countries in Europe and even the United States -- Apple's home turf -- are our primary targets," a source said to the Korea Times.

"Apple claimed the existing 3G-related patents are standard essential patents (SEPs) according to our earlier commitment to the FRAND (fair, reasonable, and non-discriminatory) terms. But the story is totally different when you talked about LTE patents. These are new and highly valued," another source speaking to the Korea Time added.

It appears that Apple will use 4G LTE with the iPhone 5, especially in the U.S. and Japan, Korea, and China. The service is still limited in the UK; however, carriers Orange and T-Mobile announced that they will be introducing 4G LTE under the new "Everything Everywhere" name. T-Mobile and Orange share cellular coverage in the UK.

Samsung was ordered to pay over $1 billion to Apple at the beginning of this month. Samsung called the result a "bad day for the American consumer," referring to Apple's dominance over smartphone patents. Samsung added it would continue to pursue Apple; this is seemingly the beginning of the backlash.

Apple is expected to launch the iPhone 5 tomorrow, Sept. 12. In many ways, from the demand to refresh iOS to the rise of Android and Windows Phone, Apple faces a degree of pressure that it has not experienced since the demand for iOS 5 to play catch-up. Apple is typically late when introducing features to iOS: just look at the Notification Bar in iOS 5.

The Samsung Galaxy S3 launched May 29 and 20 million devices have sold thus far. The device outpaced the Samsung Galaxy S2, which sold 20 million devices, according to Samsung.

Apple's event kicks off tomorrow at 10AM Pacific Time.