Washington, Aug 1 (IANS): As differences on outstanding issues remain, the US and 11 other economies participating in the Trans-Pacific Partnership (TPP) negotiations failed to reach a final deal.

"We have made significant progress" during this meeting, but there are still some issues remaining to be resolved, US trade representative Michael Froman said on Friday.

This meeting could be the final round of negotiations on the broad TPP agreement after US Congress granted the trade promotion authority to president Barack Obama, reported Xinhua news agency.

That trade authority would allow the US president to submit trade deals to Congress for an up-or-down vote without amendments, which is crucial for the swift congressional consideration of a TPP deal.

But this week's intensive negotiations were more difficult with key discrepancies in the areas of market access and intellectual property rights further postponing the finalisation of the ambitious Asia-Pacific trade deal.

Froman said trade ministers will continue to engage in the coming period, but there's not an exact date set for the next round of negotiations.

The TPP, believed to be the world's biggest trade agreement in the past two decades that covers about 40 percent of global economic output, is central to the Obama administration's policy of advancing economic engagement in Asia and writing the rules for international trade and investment in the 21st century.

President Barack Obama is under pressure to seal the deal and get it passed in Congress as soon as possible, securing his trade legacy before the 2016 US presidential campaign heats up.