TOKYO -- Political leaders and former heads of state from across Asia have expressed concerns over the US government's tariff policies, calling for greater unity among Asian nations to overcome shared challenges.

Speaking at the 30th "Future of Asia" international forum held in Tokyo from May 29 to 30, Singapore's Deputy Prime Minister Gan Kim Yong warned that the current global trade order is under threat.

He urged Asian countries to stand united in addressing trade issues arising from the US tariffs and emphasized the importance of expanding cooperation through the Association of Southeast Asian Nations and the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), particularly in trade and industry.

Cambodian Prime Minister Hun Manet said that trade wars undermine a free, open, inclusive, and rules-based multilateral trade system, disproportionately affecting the most vulnerable. He called for unity among nations facing tariff-related pressures.

Lao President Thongloun Sisoulith underscored the importance of peaceful coexistence and mutual respect, noting that while Laos has limited trade with the United States, high tariffs could still impact its economy and investment climate.

Vietnamese Deputy Prime Minister Nguyen Chi Dung said US tariffs are having a tangible effect on Vietnam's exports and investment.

Former Malaysian Prime Minister Mahathir Mohamad criticized the US tariff measures, saying they could harm the American economy and drive up living costs domestically.

Since its inception in 1995, the "Future of Asia" forum, hosted annually by Nikkei Inc., has served as a key platform for discussing regional cooperation.

This year's forum focused on how the region can foster prosperity and economic growth through collaboration.