Taiwan's two main opposition parties, which have vowed to renew talks with China, agreed on Wednesday to make a decision on a joint presidential ticket for January's elections, as the front-running ruling party decried interference from Beijing.

The issue of China, which views Taiwan as its territory, looms over the Jan. 13 parliamentary and presidential elections. China has stepped up military and political pressure — including high-profile war games — to press the island to accept its sovereignty claim. Taiwan rejects this claim.

Vice President Lai Ching-te, the ruling Democratic Progressive Party's (DPP) presidential candidate, has almost consistently led opinion polls, leaving candidates of the main opposition Kuomintang (KMT), Hou Yu-ih, and the Taiwan People's Party (TPP), Ko Wen-je, to battle it out for second place.