Secrecy surrounding the Prime Minister's trip to the Middle East is being questioned by National foreign affairs spokesman Wayne Mapp.
Helen Clark left on Tuesday afternoon, giving most news media about three hours' notice through a press statement of her intention to visit New Zealand Defence Force personnel inthe Middle East.
Neither she nor Defence will say which countries she is going to.
She has gone on an Air Force Boeing 757 with the Secretary of Defence, Graham Fortune, Chief of Defence Force Bruce Ferguson and deputy secretary of foreign affairs Michael Green.
Dr Mapp said the secrecy invited speculation.
The United States Secretary of State, Colin Powell, Defence Secretary Donald Rumsfeld and Deputy Defence Secretary Paul Wolfowitz had all been to the Middle East in highly publicised trips.
"Everyone knows they are going on a trip," he said. "They are signalled in advance. They have news media with them.
"Why is the New Zealand Prime Minister different?"
Just before leaving, Helen Clark said she had been working on the trip "for weeks and weeks and weeks".
"I don't like not being able to say where I am going. I try to be very transparent but just for our own safety we prefer not to be specific right now."
Defence Force spokesman Warren Inkster said the trip was considered an operational one, not a VIP one and therefore was kept "classified".
