Members of the flight attendants union at United Airlines have ratified a labor deal that guarantees a 10 percent wage hike and puts the flight attendants at United and its merger partner Continental Airlines in position to begin talks on a contract covering both groups, the union said on Tuesday.

United and Continental closed their $3.17 billion merger in 2010, forming the world's largest airline, which is known as United Airlines and owned by United Continental Holdings Inc . One of the biggest obstacles to a complete merger, however, has been the integration of two work forces with joint contracts.

The Association of Flight Attendants (AFA) said the deal puts the airline "one step closer" to completing the merger.

"This agreement is good for flight attendants and good for the company. It addresses many immediate needs identified by United flight attendants and serves as a stepping-stone to single contract negotiations with our flying partners from Continental and Continental Micronesia," said Greg Davidowitch, president of AFA at United Airlines, in a statement.

AFA said 88.5 percent of its eligible members participated in the vote, and 70.4 percent cast ballots in favor of the deal.

The newly ratified contract covers 15,000 workers and includes the pay raise, job security protections and distribution of a $5,000 signing bonus.

Flight attendants on the Continental side also are represented by the AFA union and already have a labor deal.

United Continental is in talks with its other unions. The company's two pilot groups are negotiating a joint deal as are the ramp and fleet service groups, the dispatchers and the mechanics. The reservations and customer service workers are holding an election to determine union representation.

Share of United Continental were up 0.6 percent at $20.20 on the New York Stock Exchange on Tuesday afternoon.

(Reporting By Kyle Peterson in Chicago; editing by Matthew Lewis)