US telecoms giant Verizon and Internet phone pioneer Skype said Tuesday they have formed a strategic alliance to make Skype's services available to Verizon's smartphone users.

"Skype mobile on Verizon Wireless changes the game," Verizon chief marketing director John Stratton said.

"For Verizon Wireless' more than 90 million customers, Skype mobile adds great value because we're effectively giving customers ... the option to extend their unlimited calling community to hundreds of millions of Skype users around the globe," he said.

The two companies did not give financial details of the deal which was announced at the Mobile World Congress in Barcelona, Spain.

Skype bypasses the standard telephone network by sending voice and video calls over the Internet.

It allows users to call others free of charge and provides the ability to connect with land lines or mobile devices at very low rates.