Social-networking giant Facebook said it was acquiring mobile messaging company Whatsapp for $19 billion.

"WhatsApp is on a path to connect 1 billion people. The services that reach that milestone are all incredibly valuable," Facebook founder and CEO Mark Zuckerberg said.

The 5-year-old Whatsapp, which has 55 employees, has more than 450 million users, of whom 70 percent use the cross-platform real-time mobile messaging service on a daily basis.

Whatsapp has been growing rapidly, adding more than 1 million new registered users per day.

The company, whose CEO is Jan Koum, handles about 50 billion messages every 24 hours.

"I've known Jan for a long time and I'm excited to partner with him and his team to make the world more open and connected," Zuckerberg said.

The fast-growing Whatsapp is popular outside the United States, especially in Europe and Latin America, giving Facebook access to a large market of young users.

"WhatsApp's extremely high user engagement and rapid growth are driven by the simple, powerful and instantaneous messaging capabilities we provide. We're excited and honored to partner with Mark and Facebook as we continue to bring our product to more people around the world," Koum, one of the company's founders, said.

As part of the deal, Koum will join Facebook's board of directors.

"The acquisition supports Facebook and WhatsApp's shared mission to bring more connectivity and utility to the world by delivering core internet services efficiently and affordably. The combination will help accelerate growth and user engagement across both companies," the social-networking giant said. EFE