Stocks closed slightly higher on Monday, shrugging off President Donald Trump's announced tariffs over the weekend targeting the European Union and Mexico. Those new levies rekindled tensions with two of the largest U.S. trade partners and threatened to raise consumer prices.

Trump’s threats of secondary tariffs are “never going to go anywhere” as long as he is unwilling to impose costs on Moscow directly, Keir Giles, a senior fellow at the London-based Chatham House think tank, told NBC News Monday.

Stocks and bonds in the U.S. are up this year, seeming to shrug off historically large tariffs even as investors remain watchful for delayed impacts of President Donald Trump’s policy changes. U.S. stocks closed higher Monday while bonds were little changed,