The US has given Mexico 45 days to reduce the number of migrants crossing its territory on their way to the US.
Mexican Foreign Minister Marcelo Ebrard on Monday gave details of a deal reached with the US to avert the imposition of tariffs on Mexican goods.
Even though no specific target has been set, the measures taken by Mexico to curb the migrant flow will be evaluated in mid-July, Mr Ebrard said.
If the number was not down by then, a regional solution would be sought.
Mr Ebrard said the agreement reached on Friday after days of "most difficult negotiation" bought Mexico time to show it could succeed in driving down the number of migrants.
He said that US negotiators had wanted Mexico to commit to "zero migrants" crossing its territory, but according to Mr Ebrard, that was "mission impossible".
Mr Ebrard said the US side also wanted to designate Mexico as a "safe third country", which would have required Mexico to take in asylum seekers heading for the US and process their claims on its own soil.
The foreign minister said that he had averted that measure for the time being: "We told them - I think it was the most important achievement of the negotiations - 'let's set a time period to see if what Mexico is proposing will work, and if not, we'll sit down and see what additional measures are needed'".
Mexico said it would deploy its National Guard throughout the country from Monday with 6,000 additional troops being sent to its southern border with Guatemala.
How did we get here?
Illegal border crossings on Mexico's northern border with the US have been on the rise again after reaching a low in US President Donald Trump's first year in office.
In February, Mr Trump declared an emergency on the US-Mexico border, saying it was necessary in order to tackle what he described as a crisis.
In May, Mr Trump threatened that 5% tariffs on Mexican goods would be imposed on 10 June and rise by 5% every month until reaching 25% in October if Mexico did not take substantial action to curb migration.
Mexico is currently one of the largest trading partners for the US, just behind China and Canada. After days of negotiations, a deal was reached on Friday which both sides hailed as a success.
But on Monday, President Trump warned that tariffs were not off the table completely, saying that if the part of the deal which required approval by Mexico's congress was not passed, the tariffs would be reinstated.
Asked about the tweet, Mr Ebrard said that he thought President Trump was referring to possible regional measures to be taken in conjunction with Central American nations from which most of the migrants hail from.
He said those measures would only be taken if the planned actions by the Mexican government, such as reinforcing its border with Guatemala, failed.
"If these measures don't work, we'd have to move to a regional model to be approved by the [Mexican] Congress, that's what he is referring to," Mr Ebrard told reporters at a news conference.
President Trump also said that Mexico would soon make "large" agricultural purchases from the US.
But when asked about that deal on Monday, Mr Ebrard said that there had been no additional agreement with the US and that the American president was likely referring to expected growth in trade following the migration deal.