Long Island Rail Road union leaders and the head of the MTA, having no plans to hold contract talks before Sunday's strike deadline, took their dueling messages to the public Tuesday.

Meanwhile, Gov. Andrew M. Cuomo downplayed the potential impact of a shutdown of the nation's busiest commuter railroad.

"Look we've had strikes before, right? And we've survived. And we've had disasters. And we know what that's like. Hurricane Sandy was a disaster and we've gone through other disasters. This is not a disaster," Cuomo said Tuesday at an event upstate. "A real pain, maybe, but not a disaster."

Cuomo's comments came as State Comptroller Thomas DiNapoli projected that an LIRR strike could cost New York $50 million a day in economic losses.

With no negotiations scheduled before LIRR workers could legally walk off the job at 12:01 a.m. Sunday, Metropolitan Transportation Authority chairman Thomas Prendergast in an open letter to LIRR riders assured commuters that the agency "remains committed to settling this matter quickly." But, he wrote, an agreement with the unions would have to be "affordable not just today, but also into the future" without putting pressure on the agency to raise fares or scale back capital investments.

"A strike would have a devastating impact," Prendergast wrote. "It's time to have productive negotiations to resolve our differences and return to what we all do best together -- serving our LIRR customers."

The letter included details of the MTA's current proposal for 17 percent raises for current workers over seven years and health care contributions of 2 percent of weekly wages. To help fund the raises, the MTA wants future workers to pay twice as much in health care costs, take twice as long to achieve top pay, and contribute to pensions permanently, instead of for 10 years, as most current workers do.

The MTA will also begin running print and radio ads Wednesday detailing its offer and asking "When is enough enough?"

The campaign comes after an abbreviated Monday negotiation session ended with the MTA rejecting the unions' latest counteroffer without presenting a counter of its own. On Tuesday, federal lawmakers urged both sides to return to the bargaining table.

"MTA cannot settle quickly if they do not wake up," said lead union negotiator Anthony Simon, who spent Tuesday visiting various union offices throughout Long Island to coordinate Sunday's possible work stoppage. "They again showed how quickly they want a strike by coming in with nothing yesterday."

The unions, following the recommendations of two federal mediation boards, want the 17 percent raises over six years, and, according to the MTA, have proposed much smaller concessions for future workers that amount to 0.15 percent savings from their previous offer.

"Nobody feels good about a strike but at the same time they know I am doing the right thing by our members," said Simon, who plans to address union members in a closed-door meeting Wednesday.

Members of Long Island's congressional delegation Tuesday also said they were "extremely disappointed" that the MTA walked away from the bargaining table without presenting its own counteroffer.

"Both sides need to be at the negotiating table nonstop to work out an agreement that keeps the transit workforce on the job and keeps service running for our constituents," Reps. Steve Israel (D-Huntington), Peter King (R-Seaford), and Tim Bishop (D-Southampton) said in a joint statement. "Both sides need to do their part to keep negotiations moving forward rather than settling in for a stalemate. A compromise must be reached."

Meanwhile, Mark Epstein, chairman of the LIRR Commuter Council, a watchdog group, reached out to Prendergast and Simon Tuesday to "relay, personally, riders' concerns if, indeed, the strike goes forward."

Epstein urged Prendergast to step up communications to riders about the agency's plans, including with posters at stations. He also received assurance from Simon that unions would not take actions that would impact riders before Sunday.