Acting Energy and Resources Minister Hekia Parata says the Government will not consider changing its position on deep sea oil drilling.
Several boats are on their way from Auckland to the East Cape to try to stop Brazilian oil company Petrobras from beginning seismic surveying.
More than 200 supporters were at Princes Wharf on Sunday to send off the flotilla.
Environmental groups and Maori taking part want the Government to reverse a decision last year to sell off rights to explore for oil.
But Ms Parata says after the global recession and the recent earthquakes in Canterbury, there is a duty to explore every opportunity to strengthen the economy.