By Eli Watkins, CNN

(CNN) -- The Mexican ambassador to the US said Tuesday that President Donald Trump's apparent call for the US military to guard the US-Mexico border is an unwelcome one.

"It's certainly not something that the Mexican government welcomes, but as soon as we have further clarification, we can expect to have a better idea of where we are," Ambassador Gerónimo Gutiérrez said in an interview with CNN's Christiane Amanpour.

The Mexican ambassador stressed that his government is still trying to clarify what exactly Trump meant.

Gutiérrez made his comments in response to Trump's claim earlier on Tuesday that he would have the US military guard the nation's southern border until his proposed wall is built. Although Trump wasn't specific about what the troops' scope and authority would be, both Presidents Barack Obama and George W. Bush oversaw temporary deployments of National Guard troops to the border during their tenures.

The Mexican government has asked for formal clarification on Trump's comments, but Gutiérrez also said he had spoken with US Homeland Security Secretary Kirstjen Nielsen. He said he expected clarification within a few hours and supposed it was similar to previous moves by the US.

"The (US) National Guard has been called before in different instances in past years in a supportive role," Gutiérrez said. "I would assume that that's what we're looking at."

In the interview, Gutiérrez also responded to Trump's repeated statements about a caravan of Central American migrants that reached Mexico en route to the US. Gutiérrez said the people in the caravan are "not dangerous" and that it is important to separate the "shared challenges" of transnational organized crime and other security threats from "a humanitarian situation."

Gutiérrez said likewise that the Mexican government shared a desire for a secure border with the United States, but acknowledged the two neighboring nations disagreed in major ways on how to achieve that security. He cited Trump's proposed border wall as an example and again stressed the Mexican government's position that it will not pay for Trump's wall.

"A relation like the one between Mexico and the United States needs to have spaces in order to agree to disagree," he said. "The issue of the wall is certainly one of them, and as my government has clearly expressed already, Mexico by no means would be paying for a wall."