Washington, Aug 21 : Negotiators from the US, Canada and Mexico have concluded the first round of the North American Free Trade Association (NAFTA) talks here to redo the three-nation trade pact, the media reported.

Representatives from the three countries said on Sunday that negotiations will continue at a "rapid pace", adding that "a great deal of effort and negotiation will be required in the coming months", reports CNN.

The countries "are committed to an accelerated and comprehensive negotiation process" that will establish "21st century standards" that benefit citizens, they said in a statement.

Round two of the NAFTA talks are set to be held for September 1-5 in Mexico City. The third: late September in Ottawa and round four will be held in Washington, D.C. in October.

In total, seven rounds are expected through December, CNN reported.

However, a US official cautioned that December was not a firm deadline and that talks could stretch into early 2018.

The round one of talks included each of the three sides discussing their expectations about the "rules of origins" issue, according to a Mexican government official.

No firm proposals were made.

Meanwhile, since his campaign days, US President Donald Trump has slammed NAFTA, which took effect in 1994, as detrimental to American interests and pledged to withdraw Washington from the deal unless it can be revised.

Trump said the agreement has led to massive US job losses, provided incentives for companies to relocate their operations to Mexico in search of cheaper labour and caused Washington's trade deficit with its southern neighbour to soar.

First round of NAFTA talks conclude