* Crude imports from Iran fell 32.4 pct from previous month
* Imports from Kuwait, Qatar rise sharply
* Iran accounts for 4.8 pct of Japan's April crude imports (Adds details)
TOKYO, May 31 Japan's crude oil imports from Iran fell 26.1 percent in April from a year earlier, as the world's third-largest oil consumer stares at a complete halt in imports from the OPEC member from July due to tightening Western sanctions.
Imports from Qatar and Kuwait rose 44.4 percent and 61.0 percent respectively as Japan, the world's third-largest economy, sought alternative supplies.
Iran's share of Japan's crude imports fell to 4.8 percent from 7.2 percent a year earlier, making the Islamic Republic the sixth biggest supplier to Japan, down from fourth last year.
Japanese crude buyers are making the cutbacks to comply with Western sanctions against Tehran over its disputed nuclear programme that make it tough to pay for, ship and insure oil from the Islamic Republic.
Japan's imports from Iran fell to 189,100 barrels per day (bpd) last month, against 10.2 percent rise in overall crude oil imports to 3.93 million bpd, data from the Japanese Ministry of Economy, Trade and Industry (METI) showed on Thursday.
The cuts came even after Japan secured a six-month waiver from U.S. financial sanctions on Iran in March, and despite an increase in overall oil demand after last year's Fukushima nuclear disaster.
An EU ban on insuring Iranian tankers goes into effect from July 1, effectively stopping shipments because most ships are covered by European insurers and reinsurers.
April imports from Japan's top supplier Saudi Arabia increased 9.7 percent from a year ago to 1.07 million bpd while purchases from United Arab Emirates, the No. 2 exporter to the north Asian country, rose by 20.1 percent to 1 million bpd.
Qatar and Kuwait were Japan's third and fourth-biggest suppliers in April.
In March, imports from Iran fell 36.4 percent year-on-year to 270,700 bpd.
Japan's Ministry of Finance released customs-cleared crude imports data, including those from Iran, for April on Wednesday, but the oil industry regards the METI data as the benchmark because it tracks the actual import status of oil tankers.
The Ministry of Finance data showed that customs-cleared crude imports from Iran tumbled 65.5 percent from a year earlier to 564,962 kl (118,450 bpd) in April. (Reporting by Osamu Tsukimori and Risa Maeda; Editing by Aaron Sheldrick and Himani Sarkar)