U.S. President Donald Trump said Tuesday that efforts by China to rein in North Korea have failed, suggesting he's weighing new options to deal with a regime that's vowed to develop nuclear weapons capable of striking the U.S. mainland.

"While I greatly appreciate the efforts of President Xi & China to help with North Korea, it has not worked out," Trump wrote on Twitter. "At least I know China tried!"

Trump commented the day after a 22-year-old college student died in Ohio following more than a year of imprisonment in North Korea. A State Department spokeswoman said Tuesday the U.S. was considering possible steps including a ban on Americans traveling to the country.