By Paul Lienert and David Shepardson

DETROIT/WASHINGTON (Reuters) - Honda Motor Co is expanding its recall in North America of late-model vehicles equipped with potentially defective Takata air bags, in a move that could affect around 2.3 million vehicles.

The Japanese automaker sent dealers in the United States a letter last Saturday, informing them of its intent to recall about 2 million Honda and Acura vehicles over air bag problems, a Honda dealer said on Wednesday. Automotive News had reported the upcoming recall earlier on Wednesday.

Honda spokesman Chris Martin confirmed it told dealers it was recalling an estimated 1.7 million Honda brand vehicles. The dealer notice reviewed by Reuters said the driver's "airbag inflator could produce excessive internal pressure during airbag deployment." A person briefed on the matter said the recall was expected to include about 300,000 Acura vehicles, Honda's luxury brand, in the United States.

The U.S. National Highway Traffic Safety Administration said on Wednesday it had received a recall notice from Honda but that it would not be made public until Thursday.

In Canada, the country's top safety regulator said on Monday Honda was recalling more than 269,000 cars in that country, including the 2016 Acura ILX, because the driver's air bag inflator could rupture and send metal fragments into vehicle occupants.

Most of the reported vehicles being recalled in the United States are the same models as those in the Canadian recall.

Honda has previously recalled more than 6 million vehicles in the United States since 2008 to replace Takata inflators that could rupture. Of the nine U.S. deaths connected with those inflators, eight have come in Honda vehicles.

Honda's action indicates the continuing Takata recalls may not be over.

On Tuesday, Democratic U.S. Senators Richard Blumenthal and Edward Markey urged NHTSA to recall all cars with Takata inflators. The senators estimated that 24 million such vehicles remained on U.S. roads.

On Wednesday, Democratic Senator Bill Nelson said "the never-ending flow of piecemeal recall announcements" on Takata air bags "needs to end."

Asked about a broader recall, U.S. Transportation Secretary Anthony Foxx told reporters on Tuesday that NHTSA's investigation "has not been closed. There is still ongoing work. ... We will continue to take action as we deem appropriate."

Through December, NHTSA had recalled 23 million potentially defective Takata inflators in about 19 million vehicles. Two weeks ago, Takata agreed to seek the recall of a further 5.1 million driver-side inflators.

(Reporting by Paul Lienert in Detroit and David Shepardson in Washington; Editing by Frances Kerry and Peter Cooney)