Negotiations on a contested Pacific free trade pact have apparently hit a new snag — a U.S. legislative delay in bringing forward a bill viewed as crucial to concluding the deal.

Dashing earlier expectations, the U.S. Congress has yet to submit a bill that would grant what is called Trade Promotion Authority to President Barack Obama so he can sign trade deals like the Trans-Pacific Partnership without deep legislative scrutiny.

With the clock ticking to conclude the U.S.-led TPP later this year, the uncertainty about the trade bill has confounded trade officials from the United States, Japan and the 10 other negotiating countries, observers say.