Mr Shearer also takes a more generous view towards Mana leader Hone Harawira than his predecessor Phil Goff did. Mr Goff had ruled out working with Mr Harawira in a coalition, saying he did not believe he could be trusted.
However, Mr Shearer said although he had not specifically discussed it with Mr Harawira he had talked to him at events and it was "perfectly amicable".
"My stance on all of the other leaders is that I don't have a history with any of them. My feeling is that I take them as I see them on face value until I've got reason not to. As far as I'm concerned I'll chat to whoever."
Soon after becoming the leader, Mr Shearer said he hoped to work with other Opposition parties more closely. He said yesterday that the Opposition parties were already working together on certain issues, such as asset sales and the sale of the Crafar Farms, including co-operating on questioning of ministers.
"I wouldn't over-egg it in terms of co-operation, but when we're working on things like Crafar Farms or asset sales, there's obviously an advantage to working together or at least knowing what each other's doing ... It will be more of an issue by issue basis, than anything else."
Labour's leadership still met Green Party co-leaders regularly.
Labour has also occasionally transferred some of its allocated supplementary questions to Mr Peters.
"If there's an issue of concern to us all as Opposition parties and somebody is good at getting a line of questioning going that is getting results, then it makes good sense."
Green co-leader Russel Norman said he had also spoken to Mr Peters about the campaign against asset sales "but that's about it". In 2005, Mr Peters had objected to having the Green Party in a coalition under the then Labour Government and the Green Party was closed out. Dr Norman said he did not know if Mr Peters' views had changed since then.