Fonterra has postponed plans to put its proposals to divide the co-operative in two and float its business operations as a separate company to a vote among its members.

The world's largest dairy exporter first announced the plans back in November, arguing the move would ensure the business remained competitive in the worldwide dairy market.

The co-operative's management wants to list its business operations, with a 20% stake available to the public. Fonterra's farmer shareholders would maintain full control of the company's milk supply business and own about 80% of the listed business.

For at least two years, farmers would retain full control of both businesses before the listing of the operations unit.

Under Fonterra's plans, three-quarters of the farmers needed to approve the restructuring plans for them to go ahead and a vote was scheduled for May.

However, there has been unease among farmers of outside investors having a stake in the business.

"Our farmers are really uncomfortable about outside investors," Fonterra chairman Henry van der Heyden told the New Zealand Press Association. "For us to have gone ahead with the May vote on splitting the company, the weight of opinion would not have allowed us to get that over the line.

"We will need to spend much more time in consultation and discussion before any final deciding vote in 2010," said Mr van der Heyden.

Some 11,000 farmers own Fonterra, which was created in 2001 and is now the world's fifth-largest dairy company.