The G20 will become the G21 this year after Australia invited New Zealand to the annual meeting of global political powerhouses.
But Prime Minister Tony Abbott says Kiwi workers living in Australia will not be entitled to broader welfare benefits, despite them paying local tax.
Mr Abbott presented the G20 invitation to Prime Minister John Key at bilateral talks in Sydney on Friday.
New Zealand is not a member of the G20, which represents the world's leading developed and developing countries.
"I want the G20 to be an opportunity to not just showcase Australia, but to showcase Australasia," Mr Abbott told reporters at a joint press conference with Mr Key in Sydney.
"Effectively it will be a G21 this year."
The major G20 meetings begin in late February with a gathering of the group's finance ministers and central bankers in Sydney, and ends in Brisbane in November with the leaders' meeting.
Senior New Zealand business people will also be invited to the B20 meeting in Sydney in mid-July, a gathering of some 400 chief executives from around the world.
Mr Abbott said Australia would also host an Australasian business week.
Mr Key said he was very grateful for the invitation to be part of the G20 and it would be of economic significance to his country.
"It's a great sign of the friendship and the family existing between New Zealand and Australia," he said. However, Mr Abbott said he will not extend welfare benefits for New Zealanders living and working across the Tasman.
"Knowing just how industrious our brothers and sisters across the Tasman are, when they come to Australia I expect them to be, in Robert Menzies' immortal phrase, lifters not leaners," Mr Abbott told journalists.
He said he was pleased New Zealanders get what no other nation on earth gets when coming to Australia - automatic rights to work and an automatic right to residency.
"This is very precious," Mr Abbott said.
Mr Abbott did reaffirm an agreement made by the previous Labor government allowing New Zealanders who've spent most of their childhood in Australia to get student loans. Mr Key welcomed the confirmation.
"It is in both countries' best interest to provide educational opportunities for young people," he said. Australia also will expand its SmartGate network for arrivals and its trial of automated departure gates at Brisbane Airport, which will start in July 2014 focusing on trans-Tasman flights.
After Friday's discussion with Mr Abbott, Mr Key and his ministerial delegation met Australian cabinet ministers before attending a trans-Tasman business lunch at Sydney's Hilton hotel.
There he was told by Mr Abbott the Australian government looked to New Zealand for lessons, and that Mr Key was his political soul-mate.
"When I said on election night last year that 'Australia is under new management and open for business' I have to say I did have NZ in mind," Mr Abbott said.
In a speech, Mr Key urged those present not to lose sight of the global economic ball - China.
"Despite all the things you occasionally see and the odd jitters around the Dow Jones at the moment, the big game in town for all of us is still going to be China," Mr Key said.
Mr Key's visit will end after an Australian and New Zealand business reception at Kirribilli House.
