By Jyotsna Singh
BBC News, Delhi
Rice traders and environmentalists have issued a stark warning to the Indian government at a meeting in Delhi.
Farmers say normal rice fetches a good price in the export market
They said that trials of genetically modified (GM) rice may harm exports and jeopardise the livelihoods of millions of poor farmers.
The campaigners say that they are concerned that commercial rice crops could become contaminated by GM strains which will affect overseas sales.
They say that could lead to restrictions on Indian crops abroad.
India is one of the world's largest exporters of the long grained, aromatic Basmati rice.
Companies carrying out GM tests have faced protests in India
Small scale trials of GM strains have been carried out at 10 locations across the country since 2005.
The government allowed the trials to go ahead despite protests over trials in other GM foods such as mustard and brinjal (aubergine).
Last month however the Supreme Court suspended fresh tests on all crops pending a further court hearing.
Feelings 'running high'
Officials from the country's top rice traders' body joined forces with a prominent farmers' union and the environmental campaigning group, Greenpeace, to criticise the government's policy at a press conference in Delhi.
They urged the government to ensure that Indian rice remained GM-free.
The President of the All India Exporters' Association, Anil Adhlakha, said the trials were a matter of grave concern.
Feelings are running high on the issue.
On Saturday, nearly 400 protesting farmers set fire to a farm in the state of Haryana where tests for GM rice were being carried out.
Farmers' unions say Indian rice fetches a good price in the export market.
They insist any rejection or doubt of the GM-free status of Indian rice in the global market could threaten their trade.
They point to the European Union's decision to impose compulsory testing on all shipments of long grain rice from the US, after commercial supplies were found to be contaminated with GM strains.