Group of 20 finance leaders on Thursday focused on free trade in their meeting in Washington amid fears that the spread of protectionism following the introduction of new U.S. tariffs will hurt prospects for global economic growth.

The multilateral forum kicked off its two-day gathering in the wake of new tariffs on steel and aluminum announced by U.S. President Donald Trump that prompted retaliation from China and sparked fears of an all-out trade war.

Finance Minister Taro Aso said he told his counterparts that there would be no winners in a race to raise barriers to goods from abroad, and that such moves would roil financial markets.