Visitors to New Zealand over the next two months will be forgiven for not recognizing the national flag as the country flies two flags over official buildings and other sites.

The government announced Wednesday that the proposed alternative to the official flag will fly over 250 sites - including the iconic Auckland Harbour Bridge - alongside the current flag until the end of a referendum to choose the preferred flag in March.

The alternative flag, featuring a white stylized silver fern and the Southern Cross star formation against a blue and black background, was selected from five possible alternatives in a referendum in November last year.

"Having the two flags flying side by side around New Zealand will help people compare the designs before making a decision in the final flag referendum, which runs from March 3 to March 24," Deputy Prime Minister Bill English said in a statement.

However, campaigners for retaining the current flag accused the government and Prime Minister John Key, who early on expressed a preference for a change to a flag featuring a silver fern, of promoting the alternative.

"They have no statutory right to do it - this is just a blatant attempt by the Prime Minister to put his fern flag on the same level as our national flag," leader of the opposition New Zealand First party Winston Peters said in a statement.

"To fly the referendum flag winner beside the New Zealand flag is an exercise in deception and suggesting that it has the same status. Legally it has none," said Peters.

"What a ludicrous situation it will be having two flags flying."

In the March poll, the alternative design will go head to head with the current flag, which features the British Union Jack in the top left corner.

The winner will become or remain the official New Zealand flag.

The process has been marred by controversy and rancor among the political parties since it was initiated by Key after last year's general election.

Critics of the present flag, including Key, say it is too similar to the Australian flag and that it is a hangover from the country's colonial past.

The entire project is expected to cost over 26 million NZ dollars (16.6 million U.S. dollars).

Political opponents have described it as a waste of money and a "vanity project" of the prime minister.

(Xinhua)