Each country has its own military, which is necessary as a deterrent against invasion.

Junichiro Koizumi

Addressing a news conference after his election, Mr Koizumi promised radical reforms, including changes to the country's constitution, which formally bars Japan from maintaining military forces and using force to settle international disputes.

Mr Koizumi, 59, is expected to be approved as prime minister on Thursday.

He won a resounding victory over two other candidates after a campaign fought on economic policy.

Defeat: Former Prime Minister Hashimoto

He says he is prepared to risk short-term economic pain, including higher unemployment, in order to achieve long-term benefits.

BBC analyst William Horsley says Mr Koizumi's victory is nothing short of revolutionary in Japanese terms - a victory for clear-cut economic policies with party bosses unable to control the way their factions voted.

But after his election, he appeared to soften his stance as a mould-breaker, indicating that he was prepared to compromise on certain issues.

"Politics is about compromise," he said. "Sometimes I'll have to compromise. Sometimes I'll have to push my views."

War shrine visit

On the issue of Japan's military forces, Mr Koizumi said: "Each country has its own military, which is necessary as a deterrent against invasion."

Koizumi: "I feel growing pressure"

"We should not have a constitution under which (the Self-Defence Forces) can be deemed unconstitutional."

Mr Koizumi also said he was ready to visit Yasukuni Shrine, which venerates the 2.5 million Japanese killed in wars, including executed war criminals.

"Japan's prosperity is based on priceless lives of the victims," he told the news conference.

"I will make a visit with a pure mind when we honour the victims."

Mr Koizumi's nationalist leanings have caused unease among Asian neighbours.

China has urged Mr Koizumi not to visit the Yasukuni Shrine while South Korean political parties have also expressed concern over Mr Koizumi's wartime views.

The rise

The new leader replaces the gaffe-prone and discredited Yoshiro Mori, under whose premiership the government's popularity has plummeted.

The two-tiered vote included 141 ballots divided among the party's local branches and 346 cast by its members of parliament.

It is the individual citizens who moved politics

Junichiro Koizumi

Mr Koizumi became leader with 298 votes, ahead of former Prime Minister Ryutaro Mr Hashimoto with 155 votes and Economy Minister Taro Aso, with 31.

"This election was held against an unprecedented headwind," Mr Koizumi said in accepting the post. "I promised to change the party and to change Japan, and fortunately, many party members supported my call."

Mr Koizumi became the surprise frontrunner in the contest after a landslide victory in the poll of local party branches.

MPs had little choice but to endorse the desire for change among rank-and-file party members.

One leading LDP member welcomed this development as a sign that the feudalistic system of control of the party by faction bosses may be ending.

Battle on

Support for Mr Koizumi surged after he announced radical plans for solving Japan's long-standing economic woes, promising to tackle the huge debt burden.

Our analyst says Mr Koizumi is promising just what the financial markets and independent commentators have demanded for many years: an end to the politics of patronage and secrecy, and the start of a kind of politics based on policies to help the country out of its 10-year-long economic stagnation.

Mr Koizumi's first test will be whether he goes ahead and names a cabinet based on merit rather than, as in the past, on a strict balance among the Party factions.