Toyota Australia has been compelled to let go of its 350 workers at its Altuna manufacturing plant in Melbourne over rising dollar, according to the company president.

Toyota ended 2011 as Australia's highest-selling vehicle brand, but sales of its locally made Camry and Aurion dropped significantly last year.

Toyota president Max Yasuda said "unprecedented" operating conditions were putting pressure on the company, the Sydney Morning Herald reported.

The Australian dollar recently traded at a high of $1.05 against the US dollar.

Citing low sales volume, Mr. Yasuda told reporters he could not rule out more cuts in the future.

"What we assumed was a temporary circumstance has turned into a permanent situation," he said.

Saying it is not possible for Toyota to maintain the current size of its workforce, Mr. Yasuda assured the workers up for termination will be "supported during this process."

"Toyota Australia is facing severe operating conditions resulting in unsustainable financial returns due to factors including the strong Australian currency, reduced cost competitiveness and volume decline, especially in export markets," Mr. Yasuda said, adding that vehicle production had fallen from 149,000 cars in 2007 to 94,000 last year.

Charlie Marmara, senior convenor with the Australian Manufacturing Workers Union (AMWU), said union delegates were told about the cuts at 3.30pm (Australian time).

"I'm gutted," Marmara told AAP, noting that it is true other countries could build cars cheaper.

Mr. Marmara also said the union would now negotiate redundancy packages with Toyota.

In a TVNZ report, Manufacturing Minister Kim Carr acknowledged the cuts were part of the harsh realities of the high dollar and global financial uncertainty.

"The harsh reality of the continuing strong Australian dollar means that Toyota's export markets are under severe pressure, and they are struggling to sell enough cars to keep the Altona line at full capacity," Senator Carr said in a statement.

"Ultimately, companies have to take tough decisions based on commercial realities to ensure that their business model remains sustainable, and that is what Toyota has done today."