(Corrects size of new port to show capacity is 450,000 tonnes a year, not 45,000, in paragraph 2)
By Colin Packham
SYDNEY, Aug 20 (Reuters) - Agricultural trading house Bunge Ltd plans to build a port terminal on Australia's east coast, boosting competition for the country's largest agribusiness, GrainCorp Ltd.
Bunge Australia said on Wednesday the terminal would be built in Geelong, Victoria, with capacity to export 450,000 tonnes of grain a year.
The proposed new port is likely to fuel ongoing speculation of a renewed offer for Graincorp by Archer Daniels Midland Co , whose A$2.8 billion ($2.6 billion) bid last year was rejected by the Australian government due to a lack of competition.
The Bunge terminal will be the third to start operations or be announced for the Australian east coast, a stronghold for GrainCorp, since the bid was rejected last November.
Bunge has applied for planning permission to build its second port terminal, which would have three storage silos. Bunge opened its first Australian port in Western Australia earlier this year.
"We decided on Geelong due to the capabilities of its port, complementary infrastructure and good transport access for grain supply," Chris Aucote, Bunge general manager, said in a statement.
The bulk grain terminal is expected to open at the end of 2015, a spokesman for the company said.
The development marks yet more competition for GrainCorp, which also operates a port in Geelong, and Emerald Grain, recently wholly acquired by Japan's Sumitomo Corp.
GrainCorp's Geelong terminal has a capacity of just over 1 million tonnes, documents on the company's website shows.
"This is further evidence that grain exports from eastern Australia are highly competitive and contestable," said Angus Trigg, a GrainCorp spokesman.
"The regulation of our ports means that GrainCorp as an Australian-based company is increasingly disadvantaged against the much larger multinationals behind competing ports," he said, referring to rules that say GrainCorp must offer rivals access to its ports.
Logistics business Qube Holdings said in March that it had formed a joint venture with Noble Resources, a unit of Singapore's Noble Group, to develop a new port terminal at Port Kembla in Australia's New South Wales.
Cargill Group and Emerald Grain have been granted the option to acquire up to a 20 percent stake each in the new venture, Quattro Grain, which is expected to be operational by early 2016.
GrainCorp chairman Don Taylor said earlier this month he did not expect ADM to launch a fresh bid in the immediate future.
(1 US dollar = 1.0761 Australian dollar) (Reporting by Colin Packham; Editing by Joseph Radford and Richard Pullin)