Vice President Mike Pence defended the Trump administration’s imposition of tariffs on $250 billion in Chinese goods, saying that it was necessary because of the “tremendous barriers” Beijing put on companies entering its market.

That $250 billion figure could potentially double, Pence said in his remarks Saturday at the Asia-Pacific Economic Cooperation summit in Papua New Guinea. Pence addressed the gathering of political and business leaders from 21 Pacific Rim nations and territories early Saturday.