Stock futures pointed lower on Sunday evening as investors weighed fresh warnings on U.S. debt and the potential for President Donald Trump's trade war to heat up again. Late Friday, Moody's downgraded the U.

Investors will get the first chance to react to Moody’s downgrade of the U.S. credit rating late Friday over rising government debt and they’ll also look for more progress from President Trump on trade deals as the week kicks off.

Moody’s has downgraded the nation’s credit rating one notch to Aa1, leaving the U.S. without a top grade among any of the major rating agencies.