Washington, Jul 2 (IANS): US President Donald Trump has said he would prefer to wait until after the November mid-term congressional elections before signing an updated North American Free Trade Agreement (NAFTA).

"NAFTA, I could sign it tomorrow, but I'm not happy with it," Trump told Maria Bartiromo of the Fox Business Network on Sunday. "I want to make it more fair."

"I want to wait until after the election. You are going to have an election. I think it will be very interesting. I think it is going to be fine," Trump said.

"If they are not fine, I am going to tax their cars coming into America. That's the big one," he added.

The broadcast of the interview with Trump coincided with Canada's imposition of tariffs on select US goods in retaliation for Washington's levies on Canadian steel and aluminum.

A long-time critic of NAFTA, Trump demanded that Mexico and Canada agree to re-open the 1994 pact with an eye toward changing provisions he sees as an unfair to the US, Efe news reported.

Those talks, which began in 2017, were originally supposed to conclude before the start of 2018 in the hope of insulating the process from the US legislative ballot and Sunday's Mexican presidential election.

The front-runner in Mexico, Andres Manuel Lopez Obrador, has already said that he would name a new negotiating team for the NAFTA revision.

A number of sensitive issues remain under discussion among senior trade officials from the three countries and none of the parties has proclaimed that accord is near.