Taiwan said Monday its military planes have made about 30 flights into a part of China's newly declared air defence zone which overlaps a similar Taiwanese zone.

China's unilateral announcement on November 23 of an Air Defence Identification Zone (ADIZ) in the East China Sea has angered the United States, Japan and South Korea as well as Taiwan.

Beijing demands that all aircraft submit flight plans when traversing the zone, which covers islands disputed with Tokyo and also claimed by Taipei.

On Friday the Ma Ying-jeou administration in Taiwan, which has been pushing for detente with the mainland since 2008, launched a belated protest about the zone following mounting pressure from the opposition.

Defence Minister Yen Ming, answering questions in parliament Monday, said the Taiwanese military planes had made "around 30 flights" into the overlapping area in the past week or so.

Yen said Taiwan's air force would scramble planes should Chinese aircraft enter the overlapping area, but none had done so as yet.

But the minister said the air force would refrain from conducting bombing exercises in the area, to avoid fuelling tensions.

Japan and South Korea both said last week they had flown into the Chinese air zone without notifying Beijing, after US B-52 bombers did likewise.

Ma's administration in a statement Saturday called for a peaceful settlement of the dispute.

But the China-sceptic main opposition party, the Democratic Progressive Party, described the comments as "too weak".

The smaller but more radical Taiwan Solidarity Union filed a lawsuit against Ma, claiming that he had betrayed Taiwan's interests to China.

Taiwan's parliament has passed a bi-partisan resolution urging the government not to present flight plans to Beijing even though the island's Civil Aeronautics Administration agreed last week to do so.

China still considers Taiwan as part of its territory awaiting reunification, even though the two sides split back in 1949 at the end of a civil war.

But relations have warmed since Ma of the China-friendly Kuomintang party came to power in 2008 on a platform of strengthening trade and tourism links. He was re-elected in January 2012.