Gov. Andrew M. Cuomo struck a deal with the Bloomberg administration on Tuesday that would expand taxi service in New York by allowing livery cabs to be hailed on the street in parts of the city traditionally underserved by yellow cabs.

The agreement, which Mr. Cuomo is poised to sign into law on Wednesday and which ends months of fractious negotiations, would also create 2,000 more wheelchair-accessible yellow cabs. The auction of those medallions is expected to raise at least $1 billion for the city.

A new class of livery cab, with metered fares, credit card readers and roof lights, will begin to appear on the streets next year. The system, proposed by the Bloomberg administration, is expected to vastly expand access to taxis in northern Manhattan and the other four boroughs, a goal that has eluded the city for decades.

The deal is a political victory for Mayor Michael R. Bloomberg, who has sometimes stumbled when trying to pass major legislation in the Capitol. The plan may still face a legal challenge from the fleet owners of the yellow cab industry, a moneyed and influential group that bitterly opposed the bill, saying it would create too much competition for traditional taxis and devalue their medallions.