Rieter Holding AG (RIEN), a Swiss textile machinery-maker, will double its workforce in China to 1,800 employees over the next two years to expand in Asia, Chairman Erwin Stoller said.

Rieter may also increase staff in India by about 25 percent to 2,000 in the same period, Stoller said in an interview today at Rieter’s annual results conference in Winterthur, where it’s based.

The company got about a third of its 2011 sales from China and India. Rieter today said earnings before interest and tax rose to 112.6 million francs ($123 million) last year, missing the 123.6 million-franc average of seven analysts’estimates compiled by Bloomberg. The stock fell as much as 11 percent.

Rieter must manufacture machinery in India and China or face being undercut by competitors in those countries who do not have to pay import taxes, Stoller said. The new hires in China and India will not affect Swiss staff numbers, he said.

The company had 4,695 employees at the end of December.