Support for Japanese Prime Minister Yasuo Fukuda slid nine points to 31 percent in a poll published on Monday, as a political deadlock that has left the top central bank post vacant cast new doubts on his leadership.
The poll was the latest to show that concerns over Fukuda's inability to cope with a divided parliament where the opposition can delay laws and veto appointees were eroding his support.
About 54 percent of respondents to the poll in the Nikkei financial daily said they did not support Fukuda, the first time the figure has topped 50 percent in a Nikkei survey since the prime minister took office in September, the paper said.
Fukuda's falling popularity -- he initially boasted support rates of about 60 percent -- has sparked speculation that the ruling Liberal Democratic Party may try to replace him before an election that could come this year, although ousting an incumbent premier is difficult.
Bank of Japan Deputy Governor Masaaki Shirakawa became acting governor last week after the opposition-controlled upper house of parliament rejected two government nominees for the job.
Ruling and opposition parties are also locked in a battle over a provisional gasoline tax that the government wants to extend when it expires on March 31 to avoid revenue gaps.
The ruling bloc has called on the main opposition Democratic Party to hold talks on what it calls a compromise plan.
But a senior opposition party executive on Monday dismissed the proposal as an attempt to deceive the public because it first calls for enactment of budget-related bills including the gasoline tax in time for the start of the new fiscal year on April 1.
"This is the same as talks on not revising (the bill)," Democratic Party executive Kenji Yamaoka told reporters.
A separate poll in the Yomiuri daily found 64 percent of respondents had a low opinion of Fukuda's six months in office, and nearly 90 percent did not understand his political aims.
The Democrats, however, have not benefited from Fukuda's woes. Asked which party they supported, 30 percent of respondents to the Nikkei survey picked the Democrats while 40 percent opted for the ruling Liberal Democratic Party.
In addition, 65 percent of respondents to the Yomiuri poll said they did not rate Democratic Party leader Ichiro Ozawa highly.
About 865 voters responded to the March 21-23 Nikkei poll. The Yomiuri survey on March 15-16 covered 3,000 people.