Top congressional Republicans and Democrats say they've reached a deal to allow President Obama to negotiate trade deals subject to an up-or-down vote from Congress.

The "fast-track" legislation comes as Obama seeks a sweeping trade deal with 11 Pacific nations. It would renew presidential authority to present trade deals that Congress can endorse or reject, but not amend.

The Trans-Pacific Partnership proposes a trade agreement involving the United States, Japan, Vietnam, Canada, Mexico and seven other Pacific-rim nations.

The debate scrambles traditional partisan alliances.

Labor unions and others say the Pacific pact would hurt U.S. job growth and encourage other countries to abuse workers and the environment. The Obama administration rejects those claims, and says U.S. goods and services must have greater access to foreign buyers.