Raising concerns over India's slow pace of trade liberalisation, the United States said on Thursday that it was apprehensive about India's surplus in bilateral trade.

Alan Larson, US under secretary of state (economic-business) said, "The imbalance in our trading relationship continues to expand and India's trade surplus with US has more than tripled in the last decade and is likely to top $10 billion this year".

"Because India has only slowly opened its market to the outside world, this growing imbalance raises concerns in the US government and in American industry about India's commitment to ensure there is a level playing field," he said at the Indo-US Economic Summit in Mumbai on Thursday.

Indian merchandise exports to the US were stood at $13 billion in 2003 and were likely to reach $15 billion in 2004. At the same time, American exports to India have not fared well and have languished at $3-4 billion a year since 1995, he added.

Countering the US view, Union Minister of State in Prime Minister's Office Prithviraj Chavan said, "The country is committed to reforms including FDI (foreign direct investment) and has honoured all international commitments and will continue to do so."