(CNN) — US airline passengers who don't identify as "male" or "female" will soon have more gender options to choose when booking tickets.

The new gender options to be added include "unspecified" and "undisclosed."

Airlines for America (A4A), the industry trade group, made the announcement that A4A and International Air Transport Association members recently approved a new international standard for non-binary passengers effective June 1.

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"U.S. airlines value a culture of diversity and inclusion, both in the workplace and for our passengers, and we work hard each day to accommodate the needs of all travelers, while delivering a safe, secure and enjoyable flight experience," Airlines for America said in a statement.

Major airlines are making the additions to be more inclusive for diverse passengers and the news is being praised by advocacy groups.

"NCTE applauds the A4A for adding gender options that are reflective of the diversity of their passengers," Arli Christian spokesperson for The National Center for Transgender Equality said in a statement.

"Non-binary people face unnecessary, invasive, and discriminatory scrutiny by airlines,airports, and security services alike. A4A's work is in line with other states who offer gender neutral designations on IDs and is an important step toward ensuring safe and smooth travel for all passengers regardless of their gender."

These additions come as many states are adding more gender options on identification cards and birth certificates.

Implementation of the new gender options is up to each individual carrier, according to A4A. Alaska Airlines, American Airlines, Hawaiian Airlines, JetBlue, Southwest and United are all members of A4A.

American Airlines confirmed to CNN they are working to on implementing the change to accommodate passengers.

"In the coming weeks, customers will be able to select the gender with which they most closely identify during the booking process," United Airlines tweeted.

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Delta Airlines is not part of A4A, but they are also working on adding non-binary options for their customers.

"As part of Delta's ongoing efforts to accommodate the needs of diverse customers throughout our business, we are planning to offer a non-binary gender option during the booking process," Delta said in a statement.

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