BRUSSELS, Aug 18 (Reuters) - Belgian luxury lingerie retailer Van de Velde said on Monday it had raised its stake in the world's largest bra maker, Top Form International , to 23.3 percent from 16.4 percent.

The shares were purchased at an average of 0.5661 Hong Kong dollars per share, bringing the total cost of the operation to a counter value of 3.6 million euros, the group said in statement.

Van de Velde, which exports across the European Union, to the U.S. and southeast Asia, reported sales of 130.3 million euros in 2007.