The mayor of San Angelo, Texas, has resigned just ten days after a landslide re-election victory to pursue his relationship with his gay partner, an illegal immigrant.

J W Lown was elected in 2003 as the city’s youngest ever mayor at the age of 32. He has been re-elected three times, gaining 89 per cent of the latest vote, held ten days ago.

He told the San Angelo Standard-Times he fell in love with his partner in March, after he announced he would be standing for re-election.

It is thought the unnamed Mexican man had a student visa which has now expired.

Lown said he had chosen not to take the oath of office while “aiding and assisting” a person who was illegally in the country.

“I made the final decision when I knew it was the right decision to make for me and my partner and our future – and for the community,” he said.

He added he planned to stay in Mexico to try to obtain a visa so that his partner can return with him if “the people of San Angelo will welcome me back.”

Lown officially tendered his resignation via a letter delivered to city manager Harold Dominguez this week.

“While I know that the timing of this announcement is less than ideal, I have my own compelling reasons for making this decision,” he wrote. “I have made thousands of decisions on behalf of our community, and I weighed this decision in the same manner that I approached other decisions.”

Even if Lown married his partner by proxy in a state that allows gay marriage, the federal government does not recognise same-sex marriages for immigration purposes.