Guests use a sample phone at the launch of the HTC One smartphone in London February 19, 2013. (REUTERS/Toby Melville)

HTC Corp said its latest smartphone, the HTC One, will roll out in three countries next week, but sales will be delayed in North America and other countries in Europe and the Asia-Pacific region.

HTC, which originally said it would launch the phone in 80 countries in March, said in a statement on Friday that sales would not kick off before the end of April across Europe, North America and the Asia-Pacific region.

The smartphone maker has been under pressure from bigger rivals Apple Inc and Samsung Electronics Co.

The company said it has seen "unprecedented demand for and interest in" the new smartphone.

"We appreciate our customers' patience, and believe that once they have the phone in their hands they will agree that it has been worth the wait," HTC said.