The Galaxy S4 has reportedly become Samsung’s fastest-selling smartphone, less than three weeks after the phone's international release.

Korean news website the Chosun Ilbo reports that after shipping four million Galaxy S4 handsets globally in the first five days after its April 26 release, Samsung has gone on to sell more than 6 million Galaxy S4 smartphones thus far.

In recent weeks, the Samsung Galaxy S4 has faced limited supplies and inventory delays in several countries, including the U.S., due to “overwhelming demand,” according to Samsung. This seems to have not stopped the fourth-generation Galaxy S series smartphone from flying off the shelves (where available). Many carriers now report that supplies are being more readily shipped.

"As of Friday, we have sold more than 6 million units, and we predict that we could break the 10 million mark by as early as the end of this month," a Samsung executive told the Chosun Ilbo on May 10.

In comparison, Samsung’s last best-selling smartphone, the Galaxy S3, sold 3 million handsets in 21 days, while the Samsung Galaxy S2 sold as many phones in 55 days and the Samsung Galaxy S took 85 days to sell that many units.

Demand for the Samsung Galaxy S4 was apparent well before its release, as the smartphone garnered 10 million preorders globally in the first two weeks after its announcement, which is up from the 9 million preorders the Samsung Galaxy S3 saw in its 2012 pre-release.

What remains is to see how the Samsung Galaxy S4 will fair against the Galaxy S3 in the long run. Hailed as the best and fastest-selling smartphone in the world in 2012, the Galaxy S3 sold 20 million handsets in its first 100 days of release and more than 50 million units overall. Samsung has notably announced a lofty sales goal of 100 million Galaxy S4 handsets in 2013.

Samsung reported that it planned to ship 10 million Galaxy S4 handsets in the month following its international release, which should indicate that mobile carriers and retailers will have better availability of the phone in time. Such U.S. carriers as Verizon, Cricket and C-Spire have yet to release the Samsung Galaxy S4.