The Returned and Services Association says it cannot afford to wait until after the centenary of Anzac Day this month to take its fight against proposed changes to the country's flag.
The New Zealand Flag Referendums Bill was introduced to Parliament last month and the closing date for submissions on proposals to the justice and electoral committee is Thursday, April 23.
RSA chief executive David Moger said the timing of the flag debate was insensitive.
"We feel it's inappropriate that these submissions close two days before April 25 when we will all be standing there as dawn breaks under the New Zealand Flag," said Mr Moger.