"While some 2005 Civic models were previously included, no Accord vehicles from the listed model years were included in the previous action," Honda said in a statement.
Honda dealers will replace the passenger front airbag inflator in the affected vehicles.
Honda said it may take "several weeks" to determine the specific list of affected vehicles, but said owners will receive notification by mail within 60 days.
"Honda is announcing this action today to encourage owners to take their vehicles to an authorized Honda or Acura dealer for repair once they are able to confirm that their vehicle is included in one of these actions," it said.
A Honda spokesman did not respond immediately to a query from Edmunds asking if there are any injuries, crashes or fatalities linked to the expanded recall.
The National Highway Traffic Safety Administration last week ordered Japanese supplier Takata to expand the recall of potentially defective airbags to cover nearly 34 million vehicles, making it the largest automotive safety recall in U.S. history.
The inflators in the Takata airbags could rupture, sending metal pieces into the passenger compartment and causing serious injury or death. At least six deaths and more than 100 injuries have been linked to Takata airbag ruptures.
Honda said the vast majority of Honda and Acura vehicles affected by last week's announcement "were already covered by past recalls or safety improvement campaigns."
It added: "In fact, many of these vehicles have already been repaired. We've replaced nearly 2 million inflators since 2013, most of those in the last nine months alone."
More consumer information about the Honda passenger airbag inflator recall expansion will be available online, through Honda dealers and by phone through Honda and Acura customer service after June 15.
NHTSA said information about the Honda recall expansion is expected to be posted soon on its Recalls Spotlight microsite.
Edmunds says: Affected consumers should stay in close touch with their dealers and Honda or Acura for more information.