It had planned a December 15 closing date for the five blocks initially advertised last March. However, it now says that as a result of recent government initiatives to further encourage exploration - coupled with renewed interest in New Zealand - it is timely to offer a larger tender next year.

Crown Resources group manager Adam Feeley said the decision was a result of the government's decision to encourage bids for petroleum exploration permits through freely available, government-acquired geo-technical data; and as a consequence of recent discussions with North American exploration companies.

In September the government announced it was funding the NZ$15 million acquisition of new or re-processed seismic data to be made available to bidders for petroleum permits.

Feeley said that data fund had considerably widened the potential interest in the Northland blocks, and that data relating to Northland would be made freely available to all interested parties.

"There has been a consistent message from the exploration industry that data is critical to hastening development of New Zealand's frontier basins. It therefore would be foolish not to take advantage of the data acquisition fund to maximise interest in the Northland blocks."

The extension of time to bid on Northland would allow those interested North American companies to participate in the revised tender.

"Combining Northland with at least two other basins is likely to generate a level of interest from larger exploration companies that could not achieved by tendering it alone."

Feeley said the additional petroleum basins to be tendered would be determined from seismic studies to be undertaken over the 2004-05 summer, with an announcement on the additional blocks being made by mid-2005.