Former United States national security advisor Robert C. O’Brien called on Taiwan on Tuesday to purchase more advanced weapon systems from the U.S. and improve its trained military reserve and civilian forces to create a stronger deterrence against a Chinese invasion.

During his address made virtually at the Taiwan-U.S.-Japan Trilateral Indo-Pacific Security Dialogue conference in Taipei, O’Brien, who served as the 28th U.S. national security advisor from 2019 to 2021, said that over the years Beijing had continued to ramp up its efforts, in particular in the United Nations system, to isolate Taiwan internationally.

In addition to these efforts, China is also systematically working to entice Taiwan’s diplomatic allies to switch recognition, he said, mentioning Nicaragua, which became the latest country to do so last week, leaving Taipei with only 14 allies worldwide.

“These concerted efforts to isolate Taiwan are part of Beijing’s larger strategy in legitimizing China’s ultimate control and domination of the Chinese diaspora and reunifying China [by taking Taiwan] by military force,” he pointed out.

O’Brien recommended that Taiwan do several things to boost its overall defense.

He said first and foremost, the U.S. or its allies should provide Taiwan with a significant amount of Naval Strike Missiles and anti-ship weapons.

“These missiles can be launched from sea or land, they have a range of about 100 nautical miles, and a substantial number of them would severely threaten any Chinese amphibious force that sets sail to invade Taiwan,” said O’Brien.

Taiwan should also acquire Quickstrike air-dropped sea mines or other advanced sea mine technology from the U.S., which O’Brien said could be used to create an area denial zone in the Taiwan Strait to hamstring any Chinese amphibious force, especially if it relies heavily on converted ferries and commercial ships.

O’Brien suggested that Taiwan purchase more shoulder-fired Stinger missiles and store them at each of the roughly 2,000 police stations islandwide so it could be used against Beijing’s helicopter fleet and complicate its aerial operations in the event of a full-scale invasion.

He also urged Taiwan to improve its trained military reserve and civilian force.

“Having an organized, trained, and equipped civilian corps willing to take up arms in the event of Chinese aggression is essential to Taiwan’s defense,” he noted.

In addition to helping Taiwan with the platforms that are required to defend itself, the ex-official said that the U.S., Japan, and other nations of the Indo-Pacific and beyond must partner with Taiwan.

“I’m heartened to see small states like Lithuania and Somaliland stand up to Chinese bullying and stand beside their friends in Taiwan,” he said.

O’Brien was the fourth and final person to serve as national security advisor during the presidency of Donald Trump.

He had made similar suggestions to Taiwan earlier this year.

In response, Taiwan’s Defense Minister Chiu Kuo-cheng (邱國正) had said he would not consider putting Stinger missiles at local police stations as the weapon system was highly dangerous and should not be made accessible to untrained personnel.

“We will not do everything that foreigners suggest,” Chiu told lawmakers back in September.