China hopes to achieve substantial results from negotiations with the US over a Bilateral Investment Treaty (BIT) before August, but it is still hard for both sides to reach a consensus on the negative list issue, a former minister of commerce said on Wednesday.

"After years of negotiations, most of the core issues have been resolved, and the negative list is the only thing left to be settled," Chen Deming said on the sidelines of the Boao Forum for Asia (BFA) on Wednesday.

But what concerns Chen the most is the two sides may miss the chance of reaching an agreement before the US presidential elections enter the final phase later this year, as new uncertainties will surface.

He also noted that a gap remains between the requirements of the two countries on the negative list, and both sides need to compromise on this.

Since China and the US started the BIT negotiations in 2008, there have been 24 rounds of talks. In 2013, the two sides reached a major breakthrough when they began discussing each other's negative list, which identifies all the areas that are not open to investors.

Just last week, Premier Li Keqiang said at a news conference after the conclusion of the annual legislative session in Beijing that the two sides are making efforts to speed up the BIT talks and that China will gradually increase market access for US investors, adding that the process should be mutual.

"The US should also be more open to China, not only in terms of market access, but also in the review aspect where more transparency is needed," Chen, who is currently president of the Association for Relations Across the Taiwan Straits, said at a BFA panel discussion on Wednesday.

China became the US' largest trading partner in 2015 with bilateral trade reaching $560 billion, so a treaty between the two countries would have a major impact on the world economy, according to Chen.

He also noted that China and the US have already reached a high-standard foreign investment agreement on the BIT, though negotiations remain.

Reuben Jeffery III, former US Under Secretary of State for Economic, Business and Agricultural Affairs, told the panel that the BIT is about fairness, predictability and transparency. The agreement is aimed at removing discrimination.

"From the Chinese perspective, the country's investors will gain a higher degree of confidence as the BIT enhances their ability to control things," Jeffery said.

Merit Janow, dean of the School of International and Public Affairs at Columbia University, said the BIT will clarify the principle in both directions and support the Chinese economy's transformation.

Difficulties remain

Chen said both sides have failed to reach a consensus on the negative list.

While Chen declined to reveal the specific bottlenecks, he did mention that the media sector could be one of the areas where China cannot meet US requirements.

The State Administration of Press, Publication, Radio, Film and Television, China's broadcast regulator, issued new regulations in February, effective as of March 10, which prohibit foreign companies from publishing online content unless they have regulatory approval.

Chen also said a major problem for Chinese investments in the US is how the US views China's State-owned enterprises.

In several cases, the US government has barred Chinese companies from entering its market for allegedly having a Chinese government background.

Chen also noted that national security has been excluded from the talks.

Doug DeVos, Amway president, also said that the biggest risk to Sino-US trade and investments could be from the political side, due to factors such as the US presidential elections, which may see a decline in US government receptiveness.

Every four years, there is political volatility in the US, involving political campaigns and media hype, Jeffery said.

For instance, GOP presidential frontrunner Donald Trump spews anti-trade rhetoric, publicly threatening to impose punitive tariffs on Chinese imports.

"No matter who becomes US president, when he or she takes office, he must see the US will have to be more open to the world, otherwise the US companies and people will be affected," Chen said.