Australian Prime Minister Tony Abbott says he is certain New Zealand defence forces "will give a fine account of themselves" in the joint training mission with Australia in Iraq to help Iraq fight the Islamic State.
"They will be I suppose splendid sons of Anzacs, that's what they will be, over there in Iraq."
Mr Abbott is making a brief visit to Wellington to open the Australian memorial at New Zealand's newly opened Pukeahu National War Memorial Park, beneath the Carillion.
Mr Abbott and Mr Key held a press conference at Te Papa before heading for the memorial park, where Mr Abbott several times made pointed comparisons between the old Anzac campaign in Turkey and the joint deployment to Iraq which should be established in Camp Taji near Baghdad by the end of May.
"It is a remarkable thing to look back 100 years to that terrible baptism of fire that our two countries had on the Gallipoli peninsular on the 25th of April, 1915," Mr Abbott said.
"I think it is quite fitting that 100 years on, Australians and New Zealanders are again working for our values and our interests together in Iraq in the Building Partner Capacity mission that we are jointly engaged upon and will shortly be operational in the Middle East."
Australia is in the process of sending 330 Defence Force personnel and New Zealand 143 to support a two-year training mission at Camp Taji, 30km north of Baghdad.
Mr Key said at the press conference that he would be sticking to the two-year deployment.
"It is absolutely critical that as far as humanly possible, we stop gullible, impressionable young Australians from going to places where they could very easily be killed"
Asked about arrests in Melbourne at the weekend over an alleged Anzac Day plot against police officers, Mr Abbott said the mission was "not just a deployment for the security of Iraq, it's a deployment for the deployment of Australia and New Zealand".
Mr Key and Mr Abbott will meet again in Turkey at the weekend to commemorate the 100th anniversary of the Gallipoli landings.
Turkey is the main point of entry for foreign fighters joining Isis in Syria and Iraq, and Mr Abbott said he would be talking to the Turkish Government about what could be done "to better police that border and to better ensure that people who have no reason to be going there are prevented from being there".
"It is absolutely critical that as far as humanly possible, we stop gullible, impressionable young Australians from going to places where they could very easily be killed or they could get caught up in something that is in no one's interests."
Isis a 'death cult'
Mr Abbott said Isis was not about God or religion - it was a death cult.
To anyone who was thinking of pretending to go to Turkey while really heading off to Syria or Iraq, his message was "don't do it".
"Don't go and Australia will be doing everything we can at every level to prevent people from making that horrible, horrible trip."
Mr Key said the difference between Isis and other terrorist groups was its outreach campaign to encourage domestic terrorism and the events in Melbourne over the weekend were a clear example of that.