Moshe Kahlon, who resigned as communications minister in October 2012, three months before the last general election, held a founding meeting attended by 350 supporters at a seaside hotel on Thursday night, media reported on Friday.
"There is not one person here who does not want reform of the diplomatic situation and our relations with the world," Kahlon, formerly of Netanyahu's Likud party, said in remarks broadcast by public radio.
"There is no one here who does not want social reform."
Neither the party's name, nor details of its likely candidates, were given.
Haaretz newspaper reported in August that Kahlon intended to present his team two months before the next general election, theoretically due by January 2016.
The Jerusalem Post reported on Friday that Netanyahu had reached the conclusion that his restive five-party coalition government had become unmanageable, and that as early as next week he could announce a bill to dissolve parliament and hold a new election, probably in March.
"It is still too soon to eulogise the coalition, but if there is no choice but to advance the election, there is no reason that it would be hard to pass the bill," the paper quoted "a source close to Netanyahu" as saying.
"The final decision will be made next week. It can't go on much longer," he said.
Haaretz political commentator Yossi Verter wrote that Netanyahu might use a preliminary parliamentary reading on Wednesday of a controversial bill to enshrine in law Israel's status as the national Jewish homeland as a platform to launch his election campaign.
Critics say the new bill -- endorsed by the cabinet on Sunday -- will come at the expense of democracy and institutionalise discrimination against minorities, including Arabs.
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Netanyahu insists the law would balance Israel's Jewish and democratic characteristics.
He and former president Shimon Peres clashed over the issue on Wednesday.
"The Nation State bill is an attempt to undermine the (Israeli) Declaration of Independence for political interests," Peres said in a speech marking 41 years since the death of his political mentor and Israel's first premier, David Ben Gurion.
"The bill will damage the country both at home and abroad and it will erode the democratic principles of the state of Israel," he added.
Netanyahu said that since the 1948 founding of the Jewish state circumstances had changed, and it was necessary to bolster its character with legislation.
"When Ben Gurion proclaimed the establishment of the state of Israel the need to enact basic laws to ensure its Jewish and democratic nature was not seen," he said at the graveside memorial ceremony.
"Now there are those who challenge the Jewish character of the state of Israel -- and many are doing so -- and therefore there is a need to defend this character with the Nation State bill."
Political analysts say that Netanyahu's support for the bill is a gesture to Likud hardliners ahead of party primaries in January.
A poll published on Thursday night by Israeli financial daily Globes said Likud has been losing popularity in recent months, and the paper advised the party to "go for an early election, and quickly".
Asked by pollster Rafi Smith which party they would vote for if an election were held now, the answers predicted that Likud would win 23 seats in the 120-member Knesset, down from the 24 it scored in an October survey but dramatically down from 31 in a July Globes poll.
Likud currently holds 18 seats.
The poll, which predicted that Kahlon's new party would win nine seats, did not give the number of respondents or the margin of error.