"It's certainly something I would take seriously," he said.
"I've always said it's a great idea and what we need."
Despite his Green Party origins, Tava has close links to National Party figures and was campaign chair for National MP Erica Stanford, who holds Murray McCully's old seat of East Coast Bays.
There has been talk for some time about the possibility of other small parties to bolster National, but National will want to ensure any such party does not carve into its own vote.
Talk that a sitting National MP could set up such a party were scotched early on as too obvious and unlikely to succeed.
The options most talked about include a Christian-based party, a centrist green party, or a conservative party similar to Act or the Conservative Party. A green party is likely to have most appeal to National.
Former National Party president Michelle Boag said Tava would be the perfect person to lead a 'blue-green' party.
"Vernon is exactly the sort of person that should be involved in this because he's sensible, he's got great credentials.
"He's smart, he's got good public appeal. His green credentials are undeniable but he's got a good balanced approach," she said.
"Quite frankly, I think he could be more useful to the National Party in a third party than he would be just in a caucus of 55."
National leader Simon Bridges said it was no secret National wanted to see new parties emerge this year.
"What would be most pleasing to see is parties that are additional to National's support base. Not just for the National Party, but for the public, a genuine green party and an indigenous Māori movement are two reasonably likely scenarios this year," he said.
"I'm hearing things about that. I haven't been in any talks or seen anything concrete yet but those sorts of developments would be positive for New Zealand."
Tava stood as the Green Party candidate in the Northcote electorate in 2011.
But he switched allegiances from the Greens to National after an unsuccessful tilt at the Greens co-leadership in 2015.
He argued at the time that the party should able to work across the political spectrum.
He missed out on selection to Dan Bidois as National's candidate for the Northcote seat left vacant when former National minister Jonathan Coleman retired from politics last year. Bidois went on to win the seat.
While negotiations were being carried out following the 2017 election, there were calls for a partnership between National and the Greens. The idea won the support of high-profile political figures, including former National prime minister Jim Bolger and former Green MP Nandor Tanczos.
Although not natural political partners, it was thought the Greens would have a positive impact on National's environmental policies and National would keep business confidence up and the economy on an even keel.
Tanczos said at the time that while the Greens may be good in opposition, they would remain a small player in coalition while they relied on "discontented Labour voters" for support.
Green Party co-leader James Shaw has previously said many of National's policies were "incongruous" to Green values.
A swing party that could partner with National is the best chance it has of forming a government at the next election. Without one, it would need to poll higher than Labour and the Greens combined and New Zealand First would have to fail to meet the 5 per cent threshold to get back into Parliament.
Who is Vernon Tava?
• Aged 41. Born in Sydney, moved to NZ aged 5
• Business broker at Divest Limited, which aims to help clients buy, grow and sell businesses and companies
• Waitematā Local Board member since October 2013. Portfolios have included Heritage and Planning, Parks and Open Spaces and Transport
• Former Green Party candidate in 2011 and also made an unsuccessful tilt to getting National nomination for last year's Northcote byelection
• Previously a consultant for the Far North District Council
• Holds a Master of Law degree (with first-class honours), and has worked as a lecturer and tutor at the University of Auckland before going into practice as a solicitor
• Widely appears as a political commentator on various media platforms