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KUWAIT, April 17 (Reuters) - Kuwait reduced its crude oil output and refining production on Sunday as part of an emergency plan to help the OPEC member deal with the largest petroleum workers' strike in years.

Kuwait Oil Company (KOC) has lowered crude output to 1.1 million barrels per day (bpd) from its normal production level of about 3 million bpd, company spokesman Saad Al-Azmi said in a posting on the KOC Twitter account.

State refiner Kuwait National Petroleum Company (KNPC) is producing some 520,000 bpd, down from 930,000 before the start on Sunday of the national stoppage, state-run Kuwait news agency KUNA reported.

Mohammed Ghazi Al Mutairi, KNPC chief executive, was quoted by KUNA as affirming its "success ... in implementing the emergency plan and operating the company's three refineries".

Khaled al-Asousi, a spokesman for KNPC said without elaborating that there was an increase in fuel supply to the local market and to the ministry of electricity. Export ports were operational and tankers were loading, he said.

Oil sector spokesman Sheikh Talal al-Khaled al-Sabah said in remarks carried by KUNA that Kuwait's oil exports had not been affected by the strike. Sabah added that Kuwait was capable of fulfilling the demands of its customers.

Thousands of Kuwaiti oil and gas workers are striking to protest against a government plan for public sector pay reforms, although non-Kuwaiti workers in the industry are not on strike. Unions have not said how long the strike will last.

Kuwait's cabinet issued a statement in response to the strike saying it would hamper work in the vital sector.

In the statement carried by KUNA, the cabinet said it had authorised state oil companies to take all necessary steps to find labour and ensure production was not affected.

It also said it would take legal measures against any unacceptable practices.

Sheikh Mohammad al-Mubarak al-Sabah, minister for cabinet affairs, told Reuters the strike was illegal as union members had refused to negotiate ahead of the stoppage.

"The members of the union were contacted by the committee headed by the manpower bureau. The members of the union refused to talk with them and went on strike. So they are in breach of Kuwaiti law. They can't strike without this (attempt at discussion)," he said.

"With the oil price being what it is, and the fact that oil income is a huge part of the (national) income, it is very difficult if not impossible for the government to provide new financial incentives."

(Reporting by Sylvia Westall and Maha el Dahan; Editing by Catherine Evans) ((william.maclean@thomsonreuters.com ; +97143664253; Reuters Messaging: william.maclean.thomsonreuters.com@reuters.net: Twitter: @WMacleanR))

Keywords: KUWAIT OIL/STRIKE