KEY POINTS:
John Key's extraordinary first week as Prime Minister continues today with a visit to London where he will meet for the first time an older half-brother - just before his meeting with the Queen and British Prime Minister Gordon Brown.
Martyn Key, 68, is one of two sons from an earlier marriage of John Key's father, George. The other lives in Canada.
Herald journalist Eugene Bingham tracked down Martyn Key in an investigation into the life of the man who would be Prime Minister, published in July, and he was surprised to learn he had a famous younger brother.
One of John Key's sisters had been in touch with him 30 years before, but other than that there had been no contact.
"It took Eugene Bingham to play the dating game to get us together," the Prime Minister said yesterday. "But he [Martyn] has emailed me and I have emailed him a couple of times.
"It'll be great. I am really looking forward to it," he said shortly before leaving Peru where he has been at the Apec leaders' summit.
The two men meet at 11 pm tonight New Zealand time.
Mr Key and Mr Brown are expected to compare notes over the G20's response to the financial crisis, which Mr Brown attended, and the Apec summit.
The meeting is scheduled for the day after Mr Brown and Chancellor of the Exchequer Alistair Darling are expected to unveil a stimulus package that will cut sales tax from 17.5 per cent to 15 per cent.
Mr Key expected the discussion would be dominated by the financial crisis but would go further.
"This is a relationship of considerable proportion obviously and spans many areas and I imagine we will touch on them."
Asked if he had given thought to New Zealand's response should Nato request a bigger contribution in Afghanistan, Mr Key said he had no briefing on that but he expected to be asked at some point.
In a one-day visit, Mr Key will also meet Conservative Party leader David Cameron and London Mayor Boris Johnson, who will attend the launch of the giant promotional rugby ball for the Rugby World Cup in 2011 near the Tower of London.
Mr Key was sworn in as Prime Minister last Wednesday and left for Apec on Thursday.
He said his personal highlight at the summit was meeting United States President George W. Bush and China's President Hu Jintao.
