UPDATE 3-American Airlines, Delta revise websites to change Taiwan reference

* China had requested website changes by Wednesday

* United Airlines yet to update website

* Hawaiian, non-U.S. carriers had made changes already (Recasts, changes date, adds Delta changes)

WASHINGTON, July 25 (Reuters) - American Airlines Group Inc and Delta Air Lines changed how their websites refer to Taiwan, a move expected to be followed by United Airlines later on Wednesday in an effort to avoid Chinese penalties.

Reuters reported early on Tuesday that the three major U.S. carriers were set to change how they refer to Taiwanese airports on their websites. American Airlines confirmed the change later in the day.

A check of American Airlines' and Delta's websites on Wednesday morning showed they now only list Taipei's airport code and city, but not the name Taiwan.

Beijing has demanded that foreign firms, and airlines in particular, not refer to Taiwan as non-Chinese territory on their websites, a move described by the White House in May as "Orwellian nonsense."

China set a final deadline of July 25 for the changes, and last month rejected U.S. requests for talks on the matter, adding to tension in relations already frayed by an escalating trade conflict.

"Like other carriers, American is implementing changes to address China's request," American Airlines spokeswoman Shannon Gilson said late on Tuesday. "Air travel is global business, and we abide by the rules in countries where we operate."

Hawaiian Airlines had changed its website ahead of the deadline to showing searches for flights to Taiwan's capital Taipei as "Taipei, Taipei" in dropdown menus, Reuters reported on Tuesday morning.

United Airlines still included references to Taiwan as of early Wednesday, according to a check of its website.

The U.S. State Department and White House did not immediately respond to requests for comment late on Tuesday.

Numerous non-U.S. airlines including Air Canada, Lufthansa and British Airways had already made changes to their websites, according to Reuters checks, after China's Civil Aviation Administration sent a letter to 36 foreign air carriers earlier in the year. (Reporting by David Shepardson in Washington; additional reporting by Jamie Freed in Singapore Editing by Michael Perry, Stephen Coates and Himani Sarkar)