By Mike DeNardo

PHILADELPHIA (CBS) – The union that represents Philadelphia Public School principals has reached a tentative agreement on a new contract that contains what the union chief calls “serious concessions.”

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The cash-starved school district and the Commonwealth Association of School Administrators agreed on the tentative deal Friday night. Union president Rob McGrogan wouldn’t release details, but he says compromises were made by both sides:

“We’ve been essentially concessionary bargaining for four years now. And that’s not easy to do. In light of the circumstances in the school district, however, we’ve reached a point where, I think that what we arrived at is something that must be considered.”

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The agreement will be presented to the union’s 500 members Thursday night at Lincoln High. Principals have been working without a new contract since September. The district is still working to achieve major givebacks from its largest union, the Philadelphia Federation of Teachers.

District spokesman Fernando Gallard said the district would not comment until after the union membership meeting.

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