Prime Minister John Key says he was "quite shocked" to find during his recent trip to the UK and Europe that there is no plan for what Brexit is going to look like.
Mr Key is in Indonesia leading a high-level trade mission following a week of meetings with leaders in London, Rome and Paris.
He told a business breakfast in Jakarta that in the aftermath of Britain's decision to leave the European Union, there's plenty of uncertainty about what will happen next.
"The most significant takeaway message is no one has a clue what it's going to look like," Mr Key said on Monday morning.
"We were quite shocked, we really thought when we got up there that there would be this plan that we had just missed in the New Zealand media - there is no plan."
Mr Key went on to say that the UK government hasn't done any work on what Brexit will involve and officials were in fact stopped from doing such work.
There are also difficulties for both Britain and the EU because negotiations on new free trade deals can't get under way until the UK has finished its "divorce proceedings" from the EU, Mr Key said.
However, Mr Key said Brexit could mean Europe puts a bigger emphasis on its links with countries in Asia.