The number of people using mobile phones to make payments is expected to rise 50 percent this year to nearly 109 million with Asians leading the pack, technology research firm Gartner said Monday.

There were 70.2 million mobile payment users worldwide in 2009 and the number is expected to increase by 54.5 percent this year to 108.6 million, Gartner said.

It said mobile payment users will represent 2.1 percent of all mobile users in 2010.

Gartner said the number of mobile payment users in Asia-Pacific was expected to rise from 41.8 million in 2009 to 62.8 million in 2010.

In Europe, the Middle East and Africa, the number of mobile payment users was expected to increase from 16.8 million to 27.1 million. In North America, the number was expected to rise from 1.9 million to 3.5 million.

"We continue to see strong growth in developing markets in Asia, Eastern Europe, the Middle East and Africa for mobile payment, while adoption in North America and Western Europe lags behind due to the plentiful choices of payment instruments that consumers have," Gartner research director Sandy Shen said.

"Developing markets have found the right formula for mobile money services -- functions that users want and an ecosystem that can sustain the service," Shen said.

She said the use of mobile payment in developing markets is being driven by "unbanked and underbanked" populations that do not have access to banking infrastructure or a personal computer, making mobile an option of choice.