"It is fair enough in New Zealand, but we are all here to make the best possible impression on the Pacific that we can."
He said Mr Key should have declined to answer such questions "rather than extrapolate and put a political spin on it".
"He doesn't even understand what Labour's policy is. We have agreements with the Pacific, and those aren't going to be changing."
The mission is taking place just four months before the September election and Mr Key invited representatives of all political parties on it. Mr Shearer was selected to represent Labour, others include Green co-leader Metiria Turei and United Future leader Peter Dunne.
Mr Key first spoke about Labour's policy during a press conference with Samoa's Prime Minister Tuilaepa after Mr Tuilaepa said the restrictions would be "detrimental to New Zealand".
He has also said he hoped his chiefly title would help National secure more of the Pacific vote and that Pacific Islands Minister Sam Lotu-Iiga had been telling Samoa's politicians that the achievement of Pacific Islanders in New Zealand schools was improving under National.
Mr Key downplayed how much the trip could help National's chances among Pacific Islanders in New Zealand.
"It doesn't hurt. It demonstrates that we are connected to their country of origin. But in the end they're more likely to be focused on policies we have domestically."
He said Labour's stance was double-speak. "They want to have it both ways. They want to tell a group of people who might hear a certain message 'we'll be tougher on migration' but actually for the people who are migrants and voting for them, they want to tell them everything is okay."
Mr Shearer said Labour was not proposing any changes that would affect the Pacific, but there were other areas immigration could be tightened "and that is right for New Zealand".
Tsunami-ravaged village uses visit to thank NZ
Five years after the tsunami that took his wife, Tui, and wrecked the resort business the pair ran, Tuatagaloa Joe Annandale has moved back down to live on the seafront of Poutasi village where he is paramount chief.
John Key (centre rear) at Tui Annandale's grave. Photo / Claire Trevett
Yesterday he welcomed Prime Minister John Key to the village for an 'ava ceremony and a visit to the village's small Peace Garden to lay flowers on his wife's grave.
Mr Key was made an ali'i (high chief) of the village a few days after the 2009 tsunami when he returned to the village he had admired on his first visit only a few months earlier.
On that first visit, he saw the waterfront where most of the villagers had homes. This time, the fale fono had been rebuilt on the waterfront but the homes were gone.
Mr Key ventured further up the slopes away from the shore where new homes now house the villagers.
But Mr Annandale said he had rebuilt his home next to the sea. "And I'm hoping the rest of my village will slowly start moving back."
Mr Annandale said the visit was a chance to thank New Zealand for its help, "in money and in kindness". Poutasi had a lot of its people on the seasonal labour scheme, and had help from the Tindall Foundation and Unitec in establishing a market garden.
