Trade union leaders at the ailing Hindustan Motors (HM) on Saturday expressed disappointment over the management's decision to sell the iconic Ambassador brand to French auto major Peugeot SA.

They said the "intuition of the management" is to sell off everything and "deprive workers".

The C.K. Birla controlled Hindustan Motors executed an agreement with Peugeot SA on Friday to sell the Ambassador brand, including trademarks, to the French auto maker for Rs 80 crore.

"The sale of the Ambassador brand shall be effective upon fulfilment of the terms of conditions as prescribed in the agreement," the company said.

"It is disappointing that the management has sold the brand Ambassador while dues to the workers still remain unresolved. They deprive workers," Intuc-affiliated HM Employees' Union General Secretary Ajit Chakraborty told media.

"About 600 workers in the Uttarpara plant, who did not avail VRS scheme are really suffering. Those who opted for the scheme have not yet realised their gratuity," Chakraborty said.

"The intuition of the management is to sell of everything. We have moved the High Court protesting various moves of the management," CITU-affiliated HM Workers' Union Vice President Manindra Chakrabarty told media.

"We have demanded that the suspension of work notice at Uttarpara plant in West Bengal be termed illegal. Operation must commence at the unit and payment of dues of all the workers be made," he added.

"The Ambassador has been an iconic brand and a surplus asset with us," said a spokesperson from HM.

"We were looking for a suitable opportunity and found the right buyer in the PSA Group. We intend to use the proceeds from the sale in clearing dues of employees, lenders and other outstandings," the spokesman said.

In May 2014, the auto maker had suspended operations in Uttarpara plant and stopped manufacturing cars with the brand about three years ago.

The Ambassador brand was born in 1957 when the automaker launched the Morris Oxford series II (Landmaster) anew and it was being produced at Uttarpara unit.

The C.K. Birla group and Peugeot SA signed a partnership deal with an investment close to Rs 700 crore in a vehicle assembly plant and powertrain manufacturing unit in Tamil Nadu.