The world's top LNG exporter Qatar is pumping growing amounts of helium as a by-product of gas output and aims to become the world's second largest  helium producer with a new plant, its energy minister said.

Qatar exports liquefied natural gas (LNG) with gas output from its giant North Field, the world's largest known pure natural gas reservoir.

Helium is used in medical diagnostics such as MRI scanners and has industrial applications for semiconductor processing, fiber optics and welding. It is the second most abundant element in the universe after hydrogen.

The Gulf Arab state's second helium plant would come on line in 2013 and purify and liquify helium recovered from the North Field, Energy Minister Abdullah al-Attiyah said on Thursday.

The volume of sales gas from the Qatar 2 Helium Project would be 1.3 billion cubic feet per year, Attiyah said. It would make Qatar second only to the United States in helium output, he added.

'Helium is rarely found in quantities large enough to justify economic extraction,' Attiyah said. 'Since 2000, world demand for helium has increased by about 20 percent - the bulk of this increasing demand can be met from Qatar's North Field for many years.'

Worldwide demand for helium stands at around 6 billion cubic feet per year, according to Qatari LNG producer RasGas, which would manage the helium plant.

Qatar's first helium facility came on stream in 2005 with a capacity of 700 million cubic feet per year.-Reuters