Palm oil giant Wilmar…denied accusations by a rights group that it had intimidated workers in an attempt to cover up a string of labour abuses from child labour to low wages on its Indonesian plantations.

Amnesty International in an investigation last November had found children as young as eight worked in "hazardous" conditions at palm plantations run by the Singapore-based firm and its suppliers in Indonesia.

Based on interviews with 120 workers, the rights group also claimed many of the workers worked long hours for low pay and without adequate safety equipment.

Amnesty said in a statement…that Wilmar - the world's largest palm oil processor - had asked its workers to sign a document to deny the investigation findings during a recent meeting with trade union representatives.

Wilmar rejected the claim and said the union representatives had "voluntarily" signed the letters as "a show of support" to the company…

Amnesty's investigation has found global consumer firms including Unilever, Nestle, Kellogg and Procter & Gamble, have sourced palm oil from Wilmar's plantations which are linked to the reported labour abuses.

The consumer firms have pledged to work with Wilmar to remedy any rights violations in their supply chain…