An army general has warned that China will not leave the Taiwan problem "unresolved for a long time", after the island's Beijing-friendly ruling party suffered a bruising election defeat, a state-run newspaper said.

Liu Jingsong told the annual conference of the Global Times newspaper that the Chinese government would not be afraid to use force to resolve "the Taiwan issue", the Chinese-language paper reported Saturday on its website without specifying further.

"The Taiwan issue will not remain unresolved for a long time. We will not abandon the possibility of using force; according to the law, it is also an option to resolve the issue by military means if necessary," said Liu, a former president of the influential Chinese Academy of Military Sciences.

He retired from active service with the People's Liberation Army in 1997.

"Whoever has political power in Taiwan, the only path (for the island) is to preserve the development of peaceful relations between the two sides of the strait, and eventually to bring about reunification," the general said.

Taiwan and China split in 1949 at the end of a civil war, but Beijing still claims the island as part of its territory awaiting reunification -- by force if necessary.

Taiwan's ruling Kuomintang (KMT) was dealt a crushing blow in local polls in late November when it lost five out of six large municipalities on the island, prompting Premier Jiang Yi-huah to resign and President Ma Ying-jeou to step down as KMT chairman.

The KMT's move to forge warmer ties with Beijing, and its perceived secrecy in forging deals with the mainland, was one of the core issues at stake in polls seen as foreshadowing the 2016 presidential race.

In face of the recent shakeup in Taiwan's political landscape, China "should not fear the storm" and has formed "new judgements and countermeasures", the Global Times paraphrased Liu as saying.

In March and April this year Taiwanese students staged a mass three-week sit-in in the parliament building in Taipei in protest at a proposed trade pact with the mainland.

Tense relations with China have warmed since Ma was elected in 2008 on a platform of improving cross-strait ties and reviving the slowing economy.

But with rising public anxiety over China's influence on the island, sentiment has turned against the Beijing-friendly approach. Voters say trade deals have been agreed in secret and not benefited ordinary Taiwanese people.

The opposition Democratic Progressive Party (DPP) has traditionally been sceptical over closer ties with Beijing and has criticised the KMT for lack of transparency over trade deals with China.

The KMT denies any secrecy over deals with China.