Amid voices of concern over a bill to legalise anti-gay discrimination by Arizona’s religious business owners, were those of three Republican state Senators who voted for the bill, admitting they made a “mistake”.

Senate Bill 1062 would prevent the state from taking action against individuals and businesses who refuse services to people or groups based on their religious beliefs if such enforcement would “substantially burden” the free exercise of their religion.

The bill was given final approval by the legislature on Friday, but State Governor Jan Brewer has not said whether she will sign it into law.

Now, as well as US GOP Senators John McCain and Jeff Flake having voiced their disapproval at the bill, a letter has been sent by three state Senators to say Governor Brewer should use her veto on the bill.

Bob Worsley, Adam Driggs and Steve Pierce sent the letter today urging just that, despite having joined the 17 GOP senators in voting for the bill on Friday.

“I was not comfortable’ with the vote,’ Worsley told The Associated Press. “I have not been comfortable with this for some time. I think laws are on the books that we need and have now seen the ramifications of my vote. I feel very bad and it was a mistake.”

Both Senators McCain and Flake tweeted today, offering short messages of support.

The measure has been extremely divisive, and heavily criticised by Democrats in the state.

“SB 1062 permits discrimination under the guise of religious freedom,” Senate Democratic Leader Anna Tovar said in a statement.

“With the express consent of Republicans in this Legislature, many Arizonans will find themselves members of a separate and unequal class under this law because of their sexual orientation.

“This bill may also open the door to discriminate based on race, familial status, religion, sex, national origin, age or disability.”

Arizona has a statute that defines marriage as the union of a man and a woman. The state only legalised same-sex sexual activity in 2001.

Mass protests have taken place in the state against the implementation of the bill.