Act Leader Don Brash left for London on Saturday night, in what was intended as a secret mission to discuss ways to fix the world's broken economy.
He was to have been in an ANZ Bank corporate box for Sunday's Rugby World Cup final. Instead, he will be at cruising altitude between Hong Kong and Heathrow, reliant on match updates from the pilot.
He promised he would be wearing his All Blacks jersey for the flight - but said the global economy was more important than a rugby game.
For Act, he said, the "key event" of the next few days would be the release of the Treasury's pre-election fiscal update.
There is understood to be concern within the party about the timing of the trip.
But Act president Chris Simmons said Brash's skills were in economic management, not in "glad-handing rugby players and tickertape parades" which he would happily leave to Prime Minister John Key.
Brash is expected to meet politicians and Sir Mervyn King, Governor of the Bank of England.
This week, King publicly warned that the world was suffering its most serious financial crisis since the 1930s, and perhaps ever.
Brash, a former Governor of New Zealand's Reserve Bank, will spend just two days in the UK before crossing the Atlantic for more meetings in Washington DC.
He had intended to keep the trip secret, lest it be seen as "a political stunt", but disclosed his plans after questions from the Herald on Sunday.
He had told the Act Party board about his plans, he said, and they accepted it was worthwhile taking a week out of the election campaign to get a full briefing on the crisis.
"I've been doing an awful lot of flesh-pressing in the past few months," Brash said.
"This last week, I've been in Dunedin, Wellington and Hawke's Bay. The Act Party board is acutely aware of economic policy and the challenges we face as a country."
New Zealand's government debt had not yet hit the same critical levels as the US, he said, but was rising fast.
There was only one answer: to gradually cut government spending and borrowing, thus lowering the dollar and helping Kiwi exporters.
The required fix was much the same for Britain and the US, he said.
Act MPs Rodney Hide and Roger Douglas have faced criticism for using their parliamentary travel allowance to take international holidays. But Brash, who is not an MP, said he would be funding his own trip in Air NZ premium economy class.
"I'm paying my way, personally. That probably explains why I'm not going business class."
Act's Epsom candidate John Banks endorsed his leader's trip. "I'm going to do the photo opportunity with Richie McCaw," he laughed. "I need the votes more than Dr Brash."