BRIDGEPORT — A push for Connecticut's biggest city to declare itself a sanctuary for immigrants has touched a nerve at City Hall.

Bridgeport's Democratic mayor, Joe Ganim, says the city wants to protect its most vulnerable residents but he says cities, suburbs and other communities should work together on the issue.

Ganim has expressed more optimism than others from his party about President Donald Trump. He has resisted calls to declare Bridgeport a sanctuary city, a designation embraced by San Francisco, New York and other cities even as Trump threatens to withhold their federal funding.

So when a Fairfield resident rallied at Bridgeport City Hall this week, calling upon the city to declare itself a sanctuary, Ganim staged his own protest at the Fairfield rail station. A photo he posted on social media shows him with a sign declaring "Make Fairfield a Sanctuary City!"

In an interview Thursday, Ganim said Bridgeport is a welcoming city but the sanctuary city title is divisive.

"People recognize the title 'sanctuary city' is not one that necessarily has to be adopted by the city of Bridgeport," he said. "We're a welcoming city. We're a supportive city. We're a city of immigrants."

The Fairfield resident, Ann McCarthy, was singled out by Ganim after the Connecticut Post ran a photograph of her at the Bridgeport rally. In a statement to the Post, she said she works in Bridgeport at the Child and Family Guidance Center, which provides mental health support to thousands of children and families, mostly from poor and minority groups. Many clients, she said, are terrified of deportation.

"We are seeing first-hand the crippling anxiety endured by our clients around heightened fears of deportation," she wrote to the newspaper.

Ganim said the issue is a sensitive one partly because the suburbs in wealthy Fairfield County do not face the challenges Bridgeport does as home to high numbers of poor and vulnerable residents, hospitals and courthouses.

"Bridgeporters, like anybody, resent people out of town telling us what to do," he added.

Ganim got to know Trump in the early 1990s during an earlier stint as mayor when the billionaire real estate developer was pursuing a project in Bridgeport. The mayor has said he could work with the Republican president on issues such as infrastructure.

But the Bridgeport City Council might yet take a stand against Trump. It is weighing a proposal that would prevent local police from acting as immigration agents and would bar the use of city facilities to detain immigrants for deportation.