BHP shareholders have approved the Australian giant's $34 billion merger with South African-based Billiton to form the world's largest diversified mining group.
The merger won the support of 88 per cent of those who voted, a comfortable margin on the 75 per cent required, despite union protests outside the shareholder meeting and the misgivings of some Australian investors.
Billiton shareholders approved the merger to form a company dual-listed in Sydney and London at a meeting in London on Tuesday.
Some Australian funds only reluctantly backed the merger after raising concerns BHP was giving too much to Billiton, ending up with 58 per cent of the merged group compared with some valuations that BHP should have had 65 per cent.
BHP Billiton would be among the world's top producers of aluminium, coking coal, steaming coal, copper, iron ore and titanium minerals with major interests in oil and gas, nickel, diamonds and silver.
"We're going to see one of this nation's major companies swallowed up by an upstart from South Africa that is less than half its size," said Mr Kym Winterbourne, a shareholder and BHP worker for 21 years.
"And what's more, we're going to pay a premium for the privilege of being done over," he said at the meeting.
Several hundred union workers thronged outside Melbourne Concert Hall ahead of the vote to voice their outrage at what they saw as the inevitable exit of BHP offshore, despite its decision to keep its head office in Melbourne.
"In the real world it's going to go London. You're living in fairy land if you don't think so," said Mr Sam Gadd, a construction worker.