The recently appointed head of the Ministry of Foreign Affairs and Trade says the desirability of New Zealand having a common currency with Australia needs to be considered.
The idea was ruled out by the Prime Minister during a visit to Australia last month.
Secretary of Foreign Affairs and Trade John Allen told the TVNZ programme Q+A on Sunday that the issue is still important.
"The common currency's been ruled out, but I do think that New Zealand needs to be thoughtful about being a small currency exposed to significant volatility," he said.
"When you talk to exporters, one of the primary concerns that they have is the volatility of our currency. It's one of the primary barriers that they face in entering the export market."
Mr Allen, who took up his appointment in July, also said the ministry did not advise the Government to send the SAS back to Afghanistan, but would not reveal what advice officials did give.
The Government last month approved three rotations of SAS troops over 18 months.
Mr Allen said on Sunday that NATO's International Security Assistance Force recognised the skills of the SAS and requested its help, and that from New Zealand's point of view it is important that Afghanistan is stablised.