Mr Aso's party has governed for most of the past half century
Japan's beleaguered Prime Minister Taro Aso has survived a no-confidence motion in the lower house of parliament.
But a non-binding censure motion has been adopted in the opposition-dominated upper house - heaping more pressure on Mr Aso.
Following his party's loss of control of the Tokyo municipal assembly on Sunday, Mr Aso dissolved parliament and called a general election for August.
Defeat would end the LDP's almost continuous rule for the past 50 years.
The prime minister is deeply unpopular, and there have been calls from within his Liberal Democratic Party (LDP) for Mr Aso to stand down as leader before the poll.
Japan's opposition put forward the motions to pile humiliation on Taro Aso, according to the BBC's correspondent in Tokyo, Roland Buerk.
The leader of the opposition Democratic Party of Japan, Yukio Hatoyama, told parliament that the huge sums being spent trying to boost the recession-wracked economy looked like an attempt to buy electoral support.
The lower house of parliament, which is controlled by the LDP, easily voted down the motion of no confidence by 333 to 139.
But a similar motion was passed in the opposition-dominated upper house a few hours later.
Recent newspaper opinion polls have suggested that the DPJ is well-placed to make considerable gains in the August election.
Such polls also put Mr Hatoyama ahead of Mr Aso as the people's choice for prime minister.
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