UPDATE 1-Iran oil tanker crew halts unloading in India port-sources

(Adds details, Indian trader quotes)

By Nidhi Verma

NEW DELHI Feb 13 (Reuters) - Crew members on board Iranian oil tanker Crystal have stopped unloading in India's Mangalore port in protest over non-payment of salaries, three sources said on Wednesday.

While it was unclear why the salaries had not been paid, Western sanctions, particularly from the United States and European Union, have sliced Iran's oil revenues and squeezed its financing. India was already paying for almost half of crude purchases in rupees and from Feb. 6, tighter measures have made it tougher for Iran to repatriate any funds from oil sales.

Mangalore Refinery and Petrochemicals Ltd managing director P. P. Upadhya said six crew members are on strike, although he didn't give a reason.

"About three-fourths of the vessel was unloaded and they are neither discharging the remaining cargo nor going back. But talks are in progress," Upadhya told Reuters.

A shipping source said there are six Ukrainian crew members on board the Crystal, who had told him they have not been paid for as long as four months. The source added that the crew members are refusing to accept payment in rupees.

"They have unloaded only 70-80 percent of the cargo but they refused to unload the remainder because of salary issues," the shipping source said.

The aframax vessel at Mangalore port is owned by the National Iranian Tanker Company (NITC). NITC officials were not immediately available for comment.

Last month, the Indian-owned tanker Omvati Prem delayed discharge of Iranian crude at Mangalore because of a funding issue with a Dubai-based charterer Sea Enterprises, which has links with a blacklisted Iranian company, Royal Oyster Group.

Indian refiners have been paying for 45 percent of their crude purchases in the rupee, which is restricted in trading on international markets, and the two countries have been trying to find goods that Tehran can buy to balance out the oil sales.

But Indian traders are wary of striking fresh deals with Iran due to a number of problems, including delayed payments.

"There are so many issues which make dealing with Iran very difficult. There are limitations when it comes to banks, shipping and insurance and that typically leads to inordinate delays in payments," said Vijay Setia, a leading rice exporter and former president of the All India Rice Exporters' Association.

"Iran was a leading buyer of India's rice, especially premium basmati, but exports have been facing problems and shipments have been falling," he said.

The sanctions are aimed at forcing the OPEC member to curb its nuclear programme and more than halved the country's oil exports in 2012. The West believes the programme is meant for making an atom bomb, an accusation Iran denies.

According to Mangalore port's website, the Crystal arrived on Sunday, Feb. 10, and was berthed on Feb. 11. Calls to the Mangalore Port chairman's office were not answered.

The shipping source and a trade source said that Iran had cleared payments to the sailors up to Dec. 31, but the crew had refused to discharge the remaining cargo as they had not yet received confirmation from their banks of the payments. (Additional reporting by Daniel Fineren in DUBAI; Mayank Bhardwaj in NEW DELHI and Jonathan Saul in LONDON; Editing by Michael Urquhart)