Hong Kong and Singapore have pulled out of plans to stage some matches in the 2019 Rugby World Cup to be hosted by Japan.

Japan was awarded the right to host the World Cup after insisting in what it called a "tender for Asia" that it will allocate some pool matches to Hong Kong and Singapore to help globalise the sport.

But the IRB has said matches must be staged within host nations unless there are special reasons to co-host them.

The 2019 Rugby World Cup will be the first to be staged in Asia.

"Hong Kong and Singapore have told us they are withdrawing," Japan Rugby Football Union president Yoshiro Mori said on Tuesday, according to Kyodo news agency. "Japan will host the tournament on its own."

Mori was speaking at the end of an inspection tour by IRB chairman Bernard Lapasset.

In its 2019 bid, Japan said sharing some World Cup matches with the two former British colonies would help cultivate new fans and create business opportunities in a region with emerging corporate power.

Hong Kong is home to the world's biggest rugby Sevens tournament, and Singapore is located close to the sport's superpower nations of Australia and New Zealand.

The hot tropical weather in Singapore, however, had been cited as a disadvantage for teams who might have to play there.

Meanwhile, the IRB has rallied behind Japan's preparations to host the 2019 event after the earthquake and tsunami which ravaged the country's north-east coast two months ago.

The March 11 disaster, coupled with a crisis at a crippled nuclear power plant, has already forced rugby union's world governing body to move five of the six Pacific Nations Cup matches in July from Japan to Fiji.

But Lapasset said: "We are all right behind the Japan rugby community and the tournament and I have no doubt that Rugby World Cup 2019 will be a tournament that Japan and the global rugby family will be proud of.

"Rugby is built on the values of solidarity and friendship and I know that the JRFU has been overwhelmed by the messages of support and sympathy from the global rugby family."

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