Negotiators from the U.S. and Japan are getting down to the wire in efforts to bridge gaps if they and other countries are to reach a wide-ranging free trade agreement.

Trade representatives entered a third day of talks in Singapore without narrowing differences that need to be resolved to seal a deal on the so-called Trans-Pacific Partnership (TPP).

It now looks increasingly likely that the talks will stretch on past Tuesday’s deadline.

Negotiators from the 12 countries participating in the TPP today (Monday) took on areas such as market access and intellectual property.

Four countries including Japan and Australia tried to shake things up by making progress on customs tariff cuts.

Japanese Economy Minister Akira Amari admitted there was still a large distance between the US and Japan, but he said he would work to bridge the gap in the remaining time.

Japan wants to preserve high tariffs in five key farm categories such as rice and beef. The U.S.-led TPP insists on eliminating those trade barriers entirely.

Observers say that with each country set on preserving its advantages, the chances of the talks dragging on are looking increasingly high.