China claims self-ruled Taiwan as part of its territory, and relations between the two have plummeted in recent years.

Last week two Chinese crew members died after a boat capsized near Kinmen, an island administered by Taipei but located just five kilometres from the mainland city of Xiamen.

It was being pursued by Taiwan's coast guard for being within prohibited waters.

China announced stepped-up patrols around Taiwan's waters, and on Monday members of its coast guard briefly boarded a Taiwanese cruise ship to check the captain and passengers' details.

Taiwan's Premier Chen Chien-jen said Tuesday that both sides had been aware of "restricted and off-limits sea areas" since 1992.

"We will continue to protect these sea areas to ensure safety in our territorial waters and the rights of our fishermen," he told reporters outside Taiwan's parliament.

"We hope both sides can be rational, equitable and cooperate with each other to ensure the safety of the Kinmen-Xiamen waters so that the people from both sides of the strait can engage with each other in a healthy and orderly manner."

Taiwan's defence minister said the military would not get involved, leaving it to the coast guard to monitor waters around Kinmen, "because we want to avoid war".

"If we intervene, it will escalate the conflict which we do not want to see," Chiu Kuo-cheng told reporters.

"Let's handle the matter peacefully."

Beijing has never renounced the use of force to bring Taiwan under its control, and in recent years has ramped up the rhetoric of "unification".

It has stepped up military pressure on Taiwan by deploying warplanes and naval vessels around the island on a near-daily basis.

Last month Taiwan had a presidential election which ended in a win for the Democratic Progressive Party's Lai Ching-te -- a candidate Beijing considers a "separatist".

Taiwan's defence ministry on Tuesday said it detected 24 Chinese warplanes around the island in the 24 hours to 6 am -- a slight uptick compared with recent days.

- 'Tacit understanding' -

Relatives of the two deceased crew were expected to arrive in Kinmen on Tuesday, while authorities said the two surviving shipmates would be repatriated.

Taiwan's coast guard had defended its actions during the pursuit that led to the deadly capsizing, saying the Chinese crew refused to cooperate with law enforcement.

It is not uncommon for Chinese and Taiwanese ships to accidentally enter the other's side, and Kinmen legislator Chen Yu-jen said the mainland coast guard had boarded the tourist ship Monday after it sailed "about one kilometre" into its waters.

"When relations between the two sides were relatively peaceful, we would not board each other's boats... It's because at that time there was a tacit understanding and the two sides would not take tougher actions," she told reporters.

But now with tenser cross-strait relations, she urged Taiwan's tourist boats and fishermen to stay within their waters.

"This is the safest way," Chen told reporters.