WASHINGTON (Reuters) -- The U.S. House of Representatives advanced a two-year budget deal in a procedural vote on Wednesday, demonstrating strong support for passage of the plan, which would also avert the threat of a Treasury default as early as next week.

The vote to move the deal ahead was 392-37. A House vote on final passage is scheduled for later on Wednesday.

The deal extends the $18.1 trillion federal debt limit through March 2017 and eases automatic spending caps to add $80 billion in discretionary spending over two years, split evenly between the military and non-defense programs. It also avoids a spike in Medicare non-hospital premiums and contains the first major reforms to Social Security disability insurance since 1983.

(Reporting by David Lawder; Editing by Peter Cooney)