Smartphones running Google's Android operating system have begun outselling Apple's iPhone both in Korea and overseas.

A total of 28,900 Android-powered smartphones were sold in Korea in the first week of this month, according to handset makers and telecom providers on Tuesday. They include 20,000 units of Samsung Electronics' Galaxy A, 5,600 units of Pantech's Sirius, and 3,300 units of LG Electronics' Andro-1. In the same period 25,700 iPhones were sold.

Android smartphones have also overtaken the iPhone for second place in the U.S. market. According to market researcher NPD on Monday, Android smartphones accounted for 28 percent of the market, compared with 21 percent for the iPhone. The top-selling model in the quarter was Research In Motion's BlackBerry, which captured a 36-percent market share.