Charlene Barshefsky, senior international partner of Wilmer Cutler Pickering Hale and Dorr LLP and the US' former top trade official, said that from the US point of view, the top difficulties for the BIT talks include the negative list, performance requirements, technology transfers and IPR protection.

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On the Chinese side, the biggest issues are investment reviews and transparency.

Barshefsky added that it will be very important for the US to be totally transparent so that investors from China know what can be done easily and what is more difficult.

"Chinese companies have to become a little bit more sophisticated in the way they plan their investment for the US. Often, it's just changing the structure or laying the groundwork with regulators. That makes all the difference with respect to whether the investment will be accepted or not.

"As the US process becomes more transparent under the BIT and Chinese investors become a little bit more sophisticated, we will see even faster growth in Chinese investment in the US. The rate of growth of Chinese investment is very fast, but it is still small in relation to total investment in the US," she said.

Last year, Chinese investment in the US exceeded US investment in China for the first time.

"Chinese investment in the US reached $4.23 billion in 2013, exceeding the US investment in China, at $3.35 billion, according to China's Ministry of Commerce.

Barshefsky said that trend might continue as China boosts overseas investment and the BIT works to forge a more welcoming and comfortable investment environment while avoiding misconceptions and misunderstanding on both sides.

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