"Not all of them are moving along satisfactorily as we would like to see," Association of Southeast Asian Nations (Asean) chief Ong Keng Yong said at a business forum on the sidelines of the bloc's annual summit.

Ong said that deals with China, India, Japan, South Korea, Australia and New Zealand had hit difficulties over reaching common standards, as well as balancing the interests of different business lobbies.

"We are carrying on our negotiations with China on trade and services and investment groups," he said of the Asean-China free trade agreement, which is targeted to be struck by 2010.

"For Korea, we have moved forward, although there are still some difficulties," he said.

"For Australia and New Zealand, we have intensified our negotiations and there are various activities ongoing which will be facilitating" discussion.

With the economies of regional heavyweights Japan and India, Ong indicated discussions were tough.

"We are undergoing very hard negotiations but we believe we should be able to come up with something satisfactory that is good," he said, without elaborating.

The Asean chief said that despite the hurdles, it was vital that the free-trade agreements (FTAs) were reached.

"We are committed to concluding all these FTA negotiations because we don't just believe in the economic value of these FTAs, we believe that the FTAs will help Asean to secure our future and compete well with the rest of the competitors in the globalised economies," he said.

Underlining the difficulties, Thailand on Friday refused to sign a trade agreement between South Korea and Asean, baulking at Seouls insistence that rice be protected from tariff cuts.

Ong said that Asean was still optimistic that the two sides will come to an agreement on the trade accord, which is a precursor to a full FTA.

"There will be problems but at the end of the day, it will happen in a slow way," he said.