Chief negotiators from 12 countries resumed talks Saturday in Guam on a U.S.-led Pacific free trade initiative, and will seek to narrow remaining gaps over intellectual property and other sticking points blocking a deal affecting roughly 40 percent of world trade.

The prospects of the 10-day session are unclear, however, as the U.S. Congress has yet to pass a fast-track trade bill seen as crucial to reaching agreement on the Trans-Pacific Partnership trade pact.

During the session, working group meetings on intellectual property and other areas will take place, as well as various gatherings of small groups of the countries engaged in the negotiations.