The international environmental group Greenpeace is blocking a ship carrying palm oil from leaving a port on Indonesia's Sumatra island. Their goal is to highlight the environmental damage caused by palm oil plantations ahead of a global climate change conference taking place in Bali next month. VOA's Nancy-Amelia Collins in Jakarta has more.

Greenpeace's Rainbow Warrior ship is blocking a tanker carrying palm oil from leaving the port of Dumai, in Riau province on Indonesia's Sumatra island.

Riau province is home to one-quarter of Indonesia's palm oil plantations and has a huge amount of peatlands that are rich in carbon.

The peatlands are drained and burned to make way for palm oil plantations - sending huge amounts of carbon dioxide into the atmosphere and contributing to global warming. This helps make Indonesia the world's third largest carbon emitter after the United States and China.

Sue Conner, Greenpeace's international forest campaigner spoke to VOA from aboard the Rainbow Warrior.

"We're highlighting the issue of how a product of palm oil is driving forest destruction and climate change," she said. "And we're coming up to the meeting in Bali, the Kyoto meeting, and we are putting out a call internationally to raise the issue that forest destruction and deforestation has got to stop because it has such a huge impact on the global climate."

An international environmental conference will be held on the Indonesian island of Bali in December. Representatives of more than 180 countries will be considering progress on the implementation of the Kyoto Protocol on climate change.

Palm oil plantations are expanding rapidly in Indonesia. Global demand for the oil is increasing because it is seen as an alternative to fossil fuels. But environmentalists say it is also driving the rapid destruction of Indonesia's dwindling rainforests.

Palm oil is used in numerous food products and consumer goods. Conner says companies that use palm oil should make sure where it is coming from.

"Huge multinational companies like Unilever, Proctor and Gamble, and Nestle are buying from companies where the palm oil in that supply chain is coming from forest and peatland destruction," she said. "What we are asking big companies to do is to agree to support a moratorium on palm oil coming from forest destruction and peatland destruction."

The blockaded ship, the MT Westama, is trying to take around 30,000 tons of palm oil to India.