BANGKOK -- U.S. President Donald Trump's national security adviser on Monday called on countries intimidated by Beijing in the South China Sea to seek arbitration, as Washington put pressure on China at one of Asia's largest diplomatic gatherings.
Robert O'Brien, who represented Trump during the ASEAN Summit and related meetings, also announced an initiative aimed at countering China's Belt and Road infrastructure program -- the latest move in the deepening rivalry between the U.S. and China in the region.
O'Brien told reporters that he met with leaders of the Association of Southeast Asian Nations and discussed matters such as the South China Sea territorial disputes, which he described as "an important issue to America."
China and several ASEAN states -- Brunei, Malaysia, the Philippines and Vietnam -- have overlapping claims in the waterway.
In August, Washington accused Beijing of blocking those countries from accessing $2.5 trillion worth of oil and gas resources in the South China Sea amid a standoff between Vietnamese and Chinese vessels in waters controlled by Hanoi. A Chinese survey ship departed the area late last month, according to reports.
"As far as intimidation" of other countries in the region by Chinese militias, the People's Liberation Army navy and the Chinese coast guard, "we don't think that's right," O'Brien said. "We think the countries ought to get along. I think they ought to go to arbitration if they've got a problem."
He cited the Philippines' arbitration case against China over Beijing's expansive "Nine-Dash Line" territorial claims in the South China Sea. A tribunal in The Hague ruled in favor of Manila in 2016, a decision Beijing rejected.
Calls for Vietnam, especially by maritime experts, to follow Philippines' move mounted during the height of the standoff.
China has said that countries not party to the territorial dispute must refrain from meddling in the issue. But O'Brien said: "I don't think the U.S. is meddling in the region. I think the U.S. is a key player in the region."
O'Brien also said the U.S., Japan and Australia debuted a program on Monday called the "Blue Dot Network," which will screen infrastructure projects in which Washington and its allies can invest.
Though O'Brien did not mention China, the national security adviser said "too much infrastructure" is being built in the region that lacks "high quality" and transparency, and places countries in "debt traps" -- common criticisms of Beijing's Belt and Road Initiative.
The Blue Dot Network also will involve other institutions like the Japan Bank for International Cooperation, the U.S. State Department said.
"Infrastructure projects that receive the blue dots are like the seal of approval for projects that are transparent, that are good projects and something that everyone can participate in -- vendors, financiers, implementers, contractors and governments," O'Brien said.
O'Brien's remarks come as Washington and Beijing move to finalize the first phase of a trade deal amid their tit-for-tat tariff war that began last year.
"We seek good relations with China," he said, "but if we see conduct that is not fair -- and especially if it's not fair to our partners and allies in the region -- we are not gonna be shy in pointing that out."