Mexico and Canada have been invited to join the US and eight Pacific Rim nations in the multi-lateral Trans-Pacific Partnership (TPP) talks which are working towards trade agreement in the Asia-Pacific region.

Negotiations between the other partners, who include Vietnam, Brunei, Chile, New Zealand, Singapore, Australia, Malaysia and Peru, have been underway since 2010.

The TPP is the first regional agreement in which the US will participate in Asia, and is a key element of the Obama Administration's efforts to boost US jobs by increasing exports.

The TPP countries have so far completed 12 rounds of negotiations, with the nine countries claiming to have made "solid progress."

However, US manufacturers, retailers and importers are divided over textile, apparel and footwear rules in the trade pact.

Broadly speaking, US fibre and textile groups want to uphold the yarn forward rule of origin, which requires all the materials that go into a garment to originate and be assembled in a TPP country to receive tariff-free treatment.

But American retailers, apparel brands, manufacturers and importers believe the rule is too restrictive, hinders new trade and investment in the sector, and renders most existing trade ineligible for preferential tariff treatment under a free trade agreement.

There are also concerns that the addition of two new participants will complicate discussions and draw out the timeframe for a successful conclusion to be reached.

The next round of negotiations is scheduled to take place from 2-10 July in San Diego, California.