NEW YORK (CBSNewYork/AP) Southwest Airlines was finalizing plans to begin flying out of Newark Liberty International Airport in March.

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A committee at the Port Authority of New York and New Jersey gave the airline preliminary approval Thursday to begin operating three gates and 18 daily flight slots previously used by United.

The agency’s board of commissioners was expected to sign off on the plan Thursday afternoon.

Under the deal, Southwest will start with six daily flights to Chicago-Midway and two to St. Louis.

In June it will add flights to Baltimore, Denver, Houston and Phoenix.

The airline has pledged to invest $2.2 million in improvements to its new gates at Newark.

United was giving up the gates and flight slots as part of its merger with Continental.

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