Mr McCully said: "I think we've had an invitation," but further discussions were needed before New Zealand made any formal commitment.
"I have taken the opportunity to outline for Dr al-Ja'afari the process that has seen the New Zealand Government already make humanitarian contributions to challenges in the region, but also in the process by which we are giving consideration to delivering other support.
"I have also taken the opportunity at exploring with the foreign minister briefly the sorts of mechanical issues that we would need to resolve in order to provide further support - especially in the training area," Mr McCully said.
Talks between Mr McCully and Dr al-Ja'afari are due to continue today, before he meets with Prime Minister John Key and Defence Minister Gerry Brownlee this afternoon.
New Zealand already has troops training for any deployment and a team of military in Iraq scoping out what role New Zealand could play and assessing factors such as safety.
Prime Minister John Key announced earlier this year that he was considering deploying troops to help train Iraqi forces but has repeatedly said it would not commit to any combat role. He has also said any contribution would be contingent on an invite from Iraq.
US President Barack Obama this week said he intended to seek permission from Congress for a three-year authorisation to step up efforts in Iraq, including deploying some special forces on the ground. The US has been undertaking air strikes since last August but has not deploy combat troops.
Mr McCully said New Zealand would make its own decisions and repeated Mr Key's assurance it would only commit to training roles 'behind the wire.' Asked about the three-year time frame President Obama had mentioned, Mr McCully said the Prime Minister had made it clear he was not interested in a long-term arrangement. Three years was "longish."
However, Labour's defence spokesman Phil Goff was sceptical about whether Obama's move would result in deeper involvement by New Zealand. He said the Government was softening up New Zealand for a greater role and predicted Mr Key would agree to consider it if there was a US request for combat involvement.
Mr McCully said he would raise the issue of corruption in the Iraqi Army - on the factors Labour have put forward as an argument against any involvement. "Those were perfectly reasonable questions given the history and we will ask those questions."
However, he said the Government had changed and a constructive approach with the new regime was needed.
In coming weeks New Zealand military personnel and their Australian counterparts would examine training options on the ground in Iraq, Mr McCully said.
However, further talks were needed to discuss the trainers' ability to protect themselves while in Iraq, he said.
The Iraqi government had confronted the threat of Isil on the ground, but needed further assistance from the international community, Dr al-Ja'afari said.
"We have taken serious steps to rebuild and reform the Iraqi armed forces," he said.
"Today Iraq is achieving ground advance in favour of the Iraqi armed forces after the support provided by the international coalition.
"We have welcomed the aerial support by the international community and other types of support, whether in providing counselling and advising, training and logistic and financial support."
Dr al-Ja'afari said although he opposed the American invasion of Iraq in 2003, he welcomed international assistance in the fight against Isil.
"The concept of occupation and invasion is quite different from the concept of military and aerial support which is based and dependant on the Iraqi sovereign support.
"I was and am still against invasion," Dr al-Ja'afari said.
"We are looking forward to receiving more support from countries including our friend New Zealand,"
He conceded that there was a level of corruption within the Iraqi armed forces, "but this does not mean that there aren't courageous Iraqi soldiers and officers to fight and sacrifice themselves".
