SK Telecom (NYSE: SKM) had such big aspirations for the U.S., and now it looks like all its efforts are for nothing.

SK Telecom’s entrance into the U.S. kicked off with a bang a few years back with Helio, a joint venture with Earthlink (NSDQ: ELNK). The South Korean telecom operator sunk hundreds of millions of dollars into that venture, only to sell the company to Virgin Mobile USA (NYSE: VM) a year ago for a paltry $39 million. This week, it’s exit is far from spectacular. The company has agreed to sell its entire 15.3 percent stake in Virgin to Sprint (NYSE: S) for much less than a fortune.

Yesterday, Sprint Nextel agreed to acquire Virgin for $483 million. SK Telecom spokeswoman Lauren Kim told the WSJ that the company’s stake in Virgin Mobile would be diluted to below 1 percent following Sprint’s acquisition. “This means there is no strategic value for us so SK Telecom has decided to sell the entire stake when market conditions are favorable.”