"If they [Epsom voters] decide to tactically vote and split their vote I wouldn't at all be unhappy."
Mr Key said he would not be voting for Mr Banks himself - as leader of the National Party, he would be voting for the National candidate, Paul Goldsmith.
Mr Banks spoke to an Epsom voter who was enjoying a cuppa himself at the Urban Cafe in Newmarket.
Mr Banks told Bennett Medary said that a vote for him would put some "reinforcing steel in the next National government policy framework".
However Mr Medary, who gave his party vote to National and his electorate vote to Rodney Hide last election, described the meeting as a stunt which would not affect his vote in this election.
About half a dozen protestors also showed up at the meeting, with one bearing a placard showing a picture of Mr Key that said "The key thing in life is sincerity, once you can fake it, you've got it made."
Labour has already responded to the meeting, with leader Phil Goff saying he did not think it will be enough to sway Epsom voters.
Mr Goff, who is at the A&P Show in Christchurch, said he did not think people would buy into the parties' plan.
"It's a rort on the system, they know it and so do New Zealanders, that's why I don't think people in Epsom will go along with it.''
Mr Goff said Mr Key had previously called Act leader Don Brash an extremist, and now he was cuddling up to the party.
"They'll be having a tea and discussing what assets they're gonna hock off next.''
Brash back on National site
While the cups of tea were a symbol of the ties between the two parties, previous links were accidentally highlighted on the National Party's website today.
The website showed a smiling Mr Brash bathed in National Party blue as part of a 2005 National Party billboard.
The photo appeared on a page urging National supporters to send National Party ecards to their friends and family.
The page was later removed, but not before Labour MP Trevor Mallard posted a screenshot of the gaff to Labour Party blog Red Alert.
Under the heading 'Nats prepare to welcome Brash back' Mr Mallard expressed his surprise that the National Party felt the need to "rehabilitate" Mr Brash.
"I didn't think he was that much of an asset but clearly their polling has him a vital cog in their machine."