Honda has asked workers at one of its Chinese factories, closed since last week by an unprecedented strike, to pledge that they will refrain from further industrial action.

The Japanese company's hard line against union activity emerged even as it struggled to resolve the wage dispute at a transmission factory that has also forced the closure of its three joint-venture car plants in Guangzhou, capital of southern Guangdong province, and Wuhan in central China.

The Honda strike coupled with recent suicides at Foxconn, the world's biggest contract maker of electronics and China's largest employer, are increasingly shining a spotlight on the conditions workers face in Chinese factories.

The “promise note” distributed to workers at Honda Automotive Components Manufacturing in Foshan, a factory town west of Guangzhou, says they “absolutely will not lead, organise or participate in work slowdowns, stoppages or strikes”.

“No one is going to sign it,” said one at a company residential compound about 10km from the transmission plant.

He and other workers either discarded the forms unsigned or defaced them. Their shifts have been suspended as negotiations between worker representatives, Honda and government mediators continued. All employees who spoke to the Financial Times asked that their names not be used for fear of retribution by Honda or the government, which keeps a tight lid on union activity through the officially sanctioned All China Federation of Trade Unions.

“The official union leaders are useless and support management,” another employee said.

The Honda workers' ability to organise themselves independently – and the effect they have had on a major multinational's overall China operations – distinguishes their action from myriad other industrial disputes that routinely flare up.

Honda workers said they earn Rmb900-Rmb1,500 ($130-$220) a month depending on experience and overtime. They are asking that monthly salaries be raised to Rmb2,000-Rmb2,500.

Honda said “a portion” of the workers had rejected two management resolution offers and negotiations were continuing.