PHILADELPHIA — Philadelphia’s main transit agency asked Thursday for assurances from the city’s striking transit union that it will suspend its walkout on Election Day if no contract agreement is reached by then. Without that promise, the agency said, it will go to court to try to force transit employees to work on Nov. 8.

The head of the Transport Workers Union local called the request ‘‘not helpful’’ and said the Southeastern Pennsylvania Transportation Authority should focus instead on reaching a settlement as the strike entered its third day.

Democratic city leaders are worried that if the city’s buses, trolleys, and subways remain idle through Election Day, some voters won’t get to the polls because of having to spend so much time getting to and from work.

Pennsylvania is a battleground state, and the vote in overwhelmingly Democratic Philadelphia is critically important to Democratic presidential nominee Hillary Clinton as she battles Republican Donald Trump.

The union’s 4,700 workers walked off the job after midnight Monday, shutting down transit service that provides about 900,000 rides a day. Pensions, work rules and health care costs are among issues on the bargaining table.

Associated Press