TOKYO, June 15 (Reuters) - Japan's lower house passed abill on Friday to provide government guarantees on insurance forIranian crude cargoes, a key step towards it becoming the first ofIran's big Asian oil buyers to get round new EuropeanUnionsanctions.

The bill will now be sent to the upper house, where oppositionparties have the majority but have signaled their support. It willbecome law by around June 27 if passed before the currentparliamentary session ends next Thursday, said a governmentofficial who requested anonymity.

The Japanese government, which has succeeded in getting awaiver from U.S. financial sanctions, wants to provide coverage ofup to $7.6 billion for each tanker carrying Iranian crude boundfor Japan in the event of accidents.

An EU ban on member countries importing Iranian oil takes effecton July 1 and includes a ban on EU insurance firms from coveringIran's exports. That is a headache for Japan, SouthKorea, China and India, which together buy twothirds of Iran's oil exports and rely on EU companies to insurethem.

EU and U.S. sanctions aim to cut the oil revenues onwhich Tehran depends to force the Islamic Republic tocurb its nuclear programme. The West suspects Iran aims to developweapons, while Tehran says it needs reactors forelectricity supplies.

Iranian oil accounted for nearly 9 percent of Japan's crudeimports last year. Japan has reduced the flow already tocomply with U.S. sanctions requiring buyers to make sizeable cuts,but wants to avoid more drastic reductions that may drive up energyimport costs and hurt the world's third-largest economy.

Refiners cut their purchases even as the country has needed moreoil to fire power stations after last year's Fukushima disastershut down the country's nuclear power capacity.

INDIA, CHINA FACE SAME ISSUE

India's government, which won an exemption to U.S. sanctionsthis week, has also been trying to figure out how it will getaround the EU sanctions.

“We are struggling to find solutions,” Oil Minister S. JaipalReddy told reporters in Vienna, where crude producers fromOPEC are meeting. The government was studying sovereign guarantees,he added.

Iran's top buyer China has yet to detail how it plansto resolve the insurance problem, but industry sources there havesaid they will find a way to keep imports flowing.

South Korea will reduce imports to zero in July due to theinsurance ban, industry sources have said. Seoul,like Tokyo, has lobbied the EU to delay or get a waiver onimplementing the ban on insurers, but is not considering stateguarantees, according to government sources there.

Those lobbying efforts have so far failed. The EuropeanUnion will not cancel or delay the embargo on Iranian oiltankers, EU Energy Commissioner Guenther Oettinger saidat an industry conference on Wednesday.

The International Energy Agency said on Tuesday thatIran's crude exports in April and May have fallen by 1 million bpdsince the end of 2011 to 1.5 million bpd andthat Tehran may need to shut in production.

China, Japan, India and SouthKorea have cut purchases by about a fifth from the 1.45million bpd they were buying a year ago ahead of the imposition ofthe sanctions.

It is the first time Japan has sought to provideguarantees on marine shipments, said an official in the country'stransport ministry, which is sponsoring the legislation. Theofficial, who helped draft the bill, said he didn't know when thelaw will be passed by parliament.