Rex Tillerson | KNKX

Rex Tillerson

Updated at 3:00 p.m. ET

President Trump announced Secretary of State Rex Tillerson was fired on Tuesday morning in a tweet that followed a year of frequent tension between the two leaders.

Prompted by a chemical weapons attack, the U.S. loosed dozens of Tomahawk missiles last week on an air base operated by Syrian President Bashar Assad, the embattled ally of Russia.

Updated at 10:35 p.m. ET

The White House says President Trump will attend a NATO meeting on May 25 in Brussels, and "looks forward to meeting with his NATO counterparts to reaffirm our strong commitment to NATO, and to discuss issues critical to the alliance, especially allied responsibility-sharing and NATO's role in the fight against terrorism."

The statement follows criticism of Secretary of State Rex Tillerson's announced intention to visit Russia in April, but not take part in a NATO foreign ministers meeting, which is also next month.

Secretary of State Rex Tillerson's inaugural trip to East Asia was marred by misunderstandings that arguably could have been avoided had Tillerson followed decades-old practice and spoken for himself — to the State Department press corps aboard his plane.

But there was no State Department press corps aboard his plane.

Tillerson had one reporter along — from a conservative-leaning news site who does not cover the State Department. In another break with tradition, the reporter did not offer a pool report to colleagues on the ground.

The effect?

Rex Tillerson concluded his first trip to Asia as secretary of state, sounding optimistic about the prospects for U.S. cooperation with China on the North Korean nuclear issue.

The upbeat notes he struck in Beijing contrasted with his remarks on Friday in Seoul about how all options, including military strikes against North Korea, remain on the table.

Updated at 5:10 p.m. ET

Secretary of State Rex Tillerson says the U.S. doesn't want to take military action against North Korea, but "all of the options are on the table" if a serious threat arises. Tillerson made his frank remarks in a visit to South Korea on Friday, a day after saying diplomatic efforts "have failed" to persuade North Korea to abandon its nuclear program.

Tillerson's Asia tour began in Japan and will end in China. The top American diplomat is traveling without a press contingent.

At a joint news conference in Mexico City on Thursday, Secretary of State Rex Tillerson acknowledged the tension between the U.S. and Mexico. After talks with his Mexican counterpart, Foreign Minister Luis Videgaray, Tillerson said that "in a relationship filled with vibrant colors, two strong sovereign countries, from time to time, will have differences."

Rex Tillerson is heading on his second foreign trip as secretary of state later this week. But as in his visit last week to Germany, Tillerson is expected to try to keep a low profile when he travels to Mexico on Wednesday.

Tillerson has said very little in public since taking office. There has been no State Department briefing since the Trump administration began a month ago.

After President-elect Donald Trump's pick for secretary of state made strong statements about China's actions in the South China Sea, Chinese officials have responded with muted, measured statements — while state-run media have warned of the potential for conflict and retaliation.

Rex Tillerson, the former Exxon Mobil CEO nominated to lead the U.S. State Department, had a confirmation hearing Wednesday. He told the Senate Foreign Relations Committee that China's actions in the South China Sea were "extremely worrisome" and compared them to Russia's annexation of Crimea.

Rex Tillerson, President-elect Donald Trump's nominee for U.S. secretary of state, is severing his ties with Exxon Mobil. The former chairman and CEO is in line to receive a $180 million retirement package.