NEW YORK (AP) — After hours of indecisive trading, stocks finished with modest gains Thursday after President Donald Trump formally ordered tariffs on steel and aluminum imports with terms that were less harsh than investors had feared.

Stocks rallied following reports that Canada and Mexico will be exempted indefinitely from the tariffs and that other countries will be invited to negotiate for exemptions as well.

Congressional Republicans and business leaders oppose the tariffs and have pushed for the administration to take a more measured approach that would invite less backlash from other c...