The 11 remaining signatories to the Trans-Pacific Partnership free trade pact are making progress toward an agreement on implementing it without the United States, probably next week, but work still needs to be done, according to the chief Japanese negotiator.

"There is a growing momentum to reach common ground and produce a good outcome," Kazuyoshi Umemoto told reporters Wednesday evening as chief negotiators for the 11 states wrapped up their three-day session near Tokyo, with a view to striking a deal on the sidelines of the Asia-Pacific Economic Cooperation ministerial meeting and summit in Vietnam due to start Wednesday.

The negotiators worked on narrowing down the list of clauses that will be suspended until such time as Washington might return to the deal, so that the 11 states' ministers and leaders can make political decisions to finalize the now 11-party pact, Umemoto said.