The pirate ransom negotiation to save the lives of 19 Chinese sailors who were onboard the Singapore-flagged cargo ship hijacked in the Gulf of Aden will last two or three months.

Shanghai Dingheng Shipping Corporation, which chartered the hijacked cargo ship named MT Golden Blessing from Singapore-based Golden Pacific International Holdings, said yesterday that two negotiation experts have been hired to handle the bargaining.

But the negotiation may take too long as the captain of the ship said food and fresh water on board could only support them for one more month. He ordered the crew to stop using fresh water in toilets, Changjiang Daily reported yesterday.

Li Jinzhong, spokesman with Shanghai Dingheng, refused to reveal details about the negotiations or how much the pirates have asked for ransom and only said that the amount was high.

The company said it keeps in touch with the hijacked Chinese crew members every day via satellite phone and they are safe so far.

The newspaper quoted a Dingheng official as saying the pirates were only after the ransom and called the abducted Chinese sailors "their friends" in the negotiation calls.

Three of the sailors have been allowed to call their family from the ship. They said the pirates did not beat them and gave their meals on time. The sailors were confined to their rooms and not allowed on deck. The ship was under the pirates' control.

The cargo ship was carrying glycol-ethylene, an anti-freeze for vehicles, from Saudi Arabia to India when it was attacked in the Gulf of Aden off Somalia on June 28.

It was the second piracy case involving China this year. A Russian carrier was seized by Somali pirates on May 5 when carrying crude oil worth US$52 million to Ningbo in east China's Zhejiang Province.

The last hijack of a Chinese crew took place on the coal ship De Xin Hai in 2009. The pirates held ship and crew for over two months until they got a ransom of US$4 million.