The "taxi of tomorrow" has hit a speed bump, as City Comptroller John Liu says he will reject the proposal unless the entire fleet is wheelchair accessible.

Featuring more passenger room and a moon roof, the Nissan NV 200 was unveiled as the city's new taxi model last month.

Liu said he will not approve the contract because it does not meet the Americans with Disabilities Act.

"We should do everything we can to ensure that New York's iconic yellow cab does not become a symbol of exclusion, one that tells people who use wheelchairs to find another ride. That's not what New York City is about," said Liu.

A City Law Department spokesperson told NY1 that Liu has no ground under the law to refuse to register the contract, and that the mayor can sign the contract into reality.

The Taxi Limousine Commission said Liu made a "mysterious and ill-informed claim," and a TLC spokesman said the posed to create 2,000 wheelchair-accessible medallion licenses, making 20 percent of the fleet accessible to those with disabilities.

The TLC also says more of these cabs will eventually be on the streets because of city incentives to taxi owners.

If approved, the new taxi will make its debut on city streets next year, in hopes of having the entire fleet converted by 2018.

Meanwhile, a federal lawsuit challenging the city issuing any taxi licenses for non-accessible cabs is winding through the courts.