Tokyo, Sep 16 (DPA) One-time opposition leader Yukio Hatoyama was elected Japan's prime minister Wednesday by parliament, ushering in a sea change in Japanese politics.

Both chambers of the Diet selected the 62-year-old self-proclaimed reformer after his Democratic Party of Japan (DPJ) won a landslide victory in Aug 30 parliamentary elections, trouncing the Liberal Democratic Party (LDP), which had governed nearly uninterrupted for more than 50 years.

The untested Hatoyama faces an uphill battle trying to implement his reform agenda, while admitting that this cabinet lacks government experience.

'We are plunging into a world of which we have no experience,' he said at his first news conference as prime minister.

'We may make mistakes as we do things by trial and error. We want the people to be tolerant... We would appreciate if the people nurture the new government with patience,' Hatoyama said.

As expected, Hatoyama named former DPJ secretary general Katsya Okada to head the foreign ministry. Okada, a stern-looking former bureaucrat in the trade ministry, is regarded as well-versed in party politics but lacks experience in international diplomacy.

The principled 56-year-old with a squeaky-clean reputation is also regarded as a possible successor of Hatoyama.

Naoto Kan was named deputy prime minister and minister of strategy. The co-founder and former leader of the DPJ is spearheading the party's ambitious plans to end the powerful bureaucracy's sway over politics.

Kan is to lead the government's new National Strategy Bureau, which is to wrest control over budget planning and day-to-day politics from the bureaucrats.

The former health minister is regarded as the right man for the job. During his tenure, he picked a fight with the bureaucracy in 1996 over a scandal involving HIV-tainted blood products.

The finance ministry will now be headed by Hirohisa Fujii, 77. A seasoned official in the ministry, Fujii is a close ally of DPJ secretary general Ichiro Ozawa, the driving force behind the party.

Ozawa is regarded as the mastermind behind the DPJ's election win.

Masayuki Naoshima, a former high-level functionary of Toyota's in-house trade union was named minister for trade and industry.

Hatoyama's cabinet faces a difficult road ahead as Japan seeks to emerge from its worst recession in the postwar era.