TOKYO - Japan is set to dissolve parliament's lower house on Friday for a Dec 16 election that is likely to return the long-dominant Liberal Democratic Party (LDP) to power with a conservative former prime minister at the helm.

However few expect the poll, three years after a historic victory swept the Democratic Party of Japan (DPJ) to power for the first time, will fix a policy stalemate that has plagued the economy as it struggles with an ageing population and security challenges.

Political experts worry former Prime Minister and head of the LDP Shinzo Abe, who polls suggest will be the next premier, will further fray ties with China.

Shinzo Abe, former Prime Minister and head of the Liberal Democratic Party (LDP), smiles as he talks with his fellow party member Shigeru Ishiba during a lower house plenary session at the parliament in Tokyo Nov 15, 2012. [Photo/Agencies]

"They will probably have the same problems of a revolving door at the top and a weak government that finds initiating tough reforms difficult and is tempted to enjoy nationalist grandstanding," said Jeffrey Kingston, director of Asian studies at Temple University's Japan campus.

Prime Minister Yoshihiko Noda, Japan's sixth prime minister in six years and the third since the DPJ's landslide election win, said on Wednesday he would call the election. He had promised three months ago to call an election in exchange for opposition support for his pet policy to double the sales tax by 2015 to curb massive public debt.

The DPJ took power in 2009 buoyed by hopes that it would keep its pledges to pay more heed to the interests of consumers and workers than corporations and give control of policy to politicians rather than bureaucrats.

Those hopes largely evaporated after the first DJP premier, Yukio Hatoyama, squandered political capital in a failed attempt to move a US airbase off Japan's Okinawa island. Successor Naoto Kan led the party to an upper house election defeat in 2010 and then struggled to cope with the huge earthquake, tsunami and nuclear crises in 2011.

Now the LDP looks likely to win the most seats in parliament's 480-member lower house. But a lack of voter enthusiasm makes it uncertain whether the party and its former junior partner, the New Komeito party, can win a majority.

If not, the LDP will need to seek another coalition partner either from among a string of new, small parties such as the Japan Restoration Party, the party of populist Osaka Mayor Toru Hashimoto, or perhaps even the DPJ or some of its members.

That latter option is less unlikely than it might seem at first blush. The LDP and DPJ lack stark policy differences, especially since Noda - a conservative on both fiscal and security matters - took the helm of what began as a centre-left party in 1996. The party's membership has been whittled by a series of defections over Noda's policies.

"The main issue (in the election) will be whether we should get rid of the 'incompetent' DPJ and bring experienced people (the LDP) back, or whether because the LDP created the mess, we should have a stronger more intelligent leader, like Hashimoto," said one ruling party lawmaker, speaking privately.