The companies overseeing construction of Maryland’s Purple Line have sued the state for breach of contract, seeking more than $100 million for its refusal to pay for delays and allegedly requiring the firms to “mask” delays in some project schedules.

The firms filed the lawsuit Tuesday as a counterclaim to one filed in August by the Maryland Transit Administration. The state is seeking more than $75 million in damages related to what it says is the firms’ illegal notice that they will leave the rail project over unpaid cost overruns.

The legal back-and-forth comes as the state and concessionaire, Purple Line Transit Partners, say they are still trying to reach a settlement over what PLTP has said are about $800 million in cost overruns stemming from more than 2 ½ years of construction delays.

A judge’s determination of whether PLTP may terminate the project’s contract due to extended delays would determine how much the state would have to pay PLTP if it leaves the project. Those costs, including paying off the firms’ construction debt, could exceed $367 million, state officials have said.

The 16-mile light-rail line between Montgomery and Prince George’s counties was initially scheduled to open in March 2022, but PLTP has said it won’t carry passengers until November 2024.

A new public accusation in the firms’ lawsuit is their assertion that Maryland officials required them to “mask” some delays in monthly project schedules in late 2016 and early 2017.

By then, the lawsuit says, construction had stalled because a judge had suspended the project’s federal environmental approval as part of a lawsuit filed by project opponents. The state also hadn’t supplied more than 100 pieces of land needed for utility easements, the lawsuit says.

State officials “directed” PLTP’s construction contractor to “mask the impacts” of the environmental approval’s suspension in three monthly updates to the project’s schedule, according to the lawsuit. The officials also directed the companies to include an “unrealistic date” in those schedules for when the federal approval would be restored, the lawsuit states.

The state also did not allow PLTP to incorporate into some monthly schedule updates the “actual forecasted dates” for when the state would provide the land for the utility easements, according to the suit.

Erin Henson, spokeswoman for the Maryland Department of Transportation, called the court filing “counterproductive” and “without merit.”

“We strongly disagree with PLTP’s characterization of the facts,” Henson said. “We remain committed to delivering the Purple Line for the citizens of Maryland and protecting the interests of the state.”

Maryland transit officials said this week that they will decide in four to six months how to proceed if PLTP quits. Some construction could continue until a new contractor or private concessionaire is hired, they said.