MEXICO CITY (Reuters) - Mexican President Andres Manuel Lopez Obrador said on Thursday he has not received an invitation to U.S. President-elect Joe Biden’s inauguration, when asked if he would travel to Washington for the Jan. 20 event.

“I don’t have an invitation, and I have decided not to leave (the country) much,” he told a regular government news conference.

Traditionally, foreign leaders are not invited to U.S. presidential inaugurations.

Lopez Obrador has only made one foreign trip in the two years he has been in office, when he visited outgoing U.S. President Donald Trump in July and praised his American counterpart for treating Mexico “with kindness and respect.”

Given that Trump had railed against Mexican migrants as rapists and drug runners, vowed to build a wall on the U.S. southern border and threatened to slap tariffs on all Mexican goods, those words jarred with critics of Lopez Obrador.

They accused the Mexican president of helping Trump’s re-election campaign. But Lopez Obrador said on Thursday he had gone because it was “very important” to attend the roll-out of a new trade deal between the United States, Mexico and Canada.

Lopez Obrador was one of the last world leaders to congratulate Biden on his victory, saying he wanted to wait for legal challenges to the U.S. election to be resolved.