Updated Dec. 5 From 2017, 5:17 p. M. Standard Time
The ambassador of Mexico in the United States, Gerónimo Gutiérrez, tells CBS News that "we now have a probability of 50-50"will be canceled. This follows a fifth round of renegotiations between the US. UU., Mexico and Canada that concluded last month in Mexico City on the free trade agreement of almost 24 years ago.
EE. UU Commercial Representative Robert Lighthizer said in a statement on November 21
Despite the uncertainty of whether NAFTA can be renegotiatedGutiérrez says that in the last year prospects and efforts towards a new agreement have increased.  Listen to Gutiérrez's interview with CBS News Radio here
"Despite the important differences, we are communicating fluently, we are attractive, and that is important," Gutierrez said. "I am moderately optimistic, in fact we can reach an agreement in the coming months."
President Trump has criticized the agreement as unfair, behind the multimillion-dollar trade deficits with the US.
Mr. Trump responded to the renegotiations on Tuesday at the White House while meeting with Senate Republicans.
"We are also going to talk about trade and NAFTA: what is happening with the NAFTA negotiations," Trump said. "We are going to look very seriously at NAFTA."
A sixth round of talks begins on January 23 in Montreal.
Meanwhile, the White House is asking Congress to fund an "initial payment" on a border wall to be included in a federal spending bill in Congress.
But Mr. Trump has promised for a long time that Mexico will pay for the construction of the wall. "In one way or another, Mexico is going to pay for the wall," he said on August 28 while speaking with journalists at the White House, along with the president of Finland Sauli Niinistö.
But Gutiérrez reaffirmed that his country will not pay for it.
"That certainly is not going to happen," he said.
Gutierrez is suggesting a toll on the border.
We need to "explore the possibility of improving that infrastructure through the use of a toll system that will help build and finance more entry point infrastructure along the border," Gutierrez said.
He said there was talk of a "user fee" that could pay for another border entry between the United States and Mexico near Tijuana and San Diego, a busy commercial route.
"There were preliminary discussions on this, and I think both parties are open," Gutierrez said.
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