With a Monday deadline looming, negotiations between SEPTA and Transport Workers Union Local 234 hit a snag on Sunday, according to transit agency officials.

SEPTA said it had offered a two-year contract with wage hikes of 2 percent the first year and 2.75 percent in the second year. But workers would have to spend an additional 1 percent of their wages on health-care premiums under the deal.

A walkout would be expected to be widely disruptive, as it would involve city transit lines, as well as suburban buses, trolleys, and the Norristown High-Speed Line. Commuter rail lines would not be impacted.

However, workers have not yet authorized a strike and could keep working without a contract while negotiations continue.

"It's not a situation where if it wasn't solved by midnight, they're automatically going on strike," SEPTA spokesman Andrew Busch said. "We're hopeful it won't happen and we're hoping to continue the progress with the negotiations."

- Aubrey Whelan