Comments from U-S Commerce Secretary Wilbur Ross have created some doubt on the feasibility of reaching an agreement on a revised NAFTA – before the unofficial deadline.

Ross says none of the hot-button issues in the negotiations – including autos, dispute resolution, labour and the so-called sunset clause – have been resolved yet.

Top American lawmakers say Thursday is the deadline for getting an agreement – in order for a vote in Congress to take place this year.

Failure to reach a deal this spring will likely delay the negotiations into next year – after a new American Congress – and a new Mexican president are sworn in.