Yesterday’s session ended in frustration at about 5:30 p.m., after workers rejected a Harvard proposal of an extra 20 cents an hour for custodians who had been at the University for over 3 years but offered no change for entry wages, Panfil said.

Union negotiators said they would keep on talking as long as discussions were progressing.

“We’re going to have to have some persistence,” said Frank Morley, a custodian at Littauer who also works a part-time job. “They’re probably waiting to see who’s going to blink first.”

According to the University’s current timetable, Harvard hopes to conclude all union negotiations by May, including those with dining workers and security guards which have not yet started.

Next year’s budgets for the University’s 11 schools are due in March, making the outcome of the negotiations a matter of urgent concern for University officials.

Union officials are now trying to turn up the heat on the administration.

Jairo Dias, an SEIU organizer, said the current contract prohibits custodial workers from striking but that the union intended to eliminate that provision from the new contract.

The Progressive Student Labor Movement, workers and union representatives organized a small demonstration on behalf of custodians in front of Au Bon Pain last night at 5:30 p.m. Protestors sat in the middle of a crosswalk in the Square for about 30 seconds, waved signs and chanted, police officers at the scene said.

Panfil said the union was organizing a larger display of civil disobedience next Tuesday but declined to comment on any specific plans. She said the nature of the demonstration would depend on progress at next week’s negotiations.

—Staff writer Elisabeth S. Theodore can be reached at theodore@fas.harvard.edu.