He told a meeting of government officials that each time the incident had involved advanced Sukhoi 27 fighters. ``Media reports have said Chinese communist fighters had occasionally flown across the middle of the Taiwan Strait,'' Lee said in an attempt to reassure the public.

``As a matter fact, they did it only twice, with one sortie going five kilometres over the middle and the other for 10 kilometers,'' he said, adding, ``They just hurried away when finding something wrong with this''.

Taipei-Beijing ties are at their lowest since the Taiwan Strait crisis in 1996 when China staged war games off Taiwan, which is considers a rebel province.

China was incensed by Lee's comment last month that he wanted a ``special state to state relationship'' with Beijing.

China has kept up a propaganda barrage against Leedescribing him as a ``historical sinner'' trying to split the island from the ``motherland''. Beijing has reaffirmed a threat to use force to prevent Taiwan declaring independence.

The Washington Post quoted an unnamed US official as saying China -- which seldom sends planes over the Straits -- had flown more than 100 sorties with three different types of aircraft since the new storm erupted.

Another official reportedly said Taiwan had flown roughly the same number of operations in the last three weeks and had also crossed the strait's center line.

Washington has expressed fears that an accidental clash could occur. At a press conference Tuesday, Taiwan's defence ministry said it had not seen any sign of military exercises on the Chinese coast facing the island. But it did confirm there had been increased air sorties and training in the strait by the People's Liberation Army (PLA).

``The Sukhoi 27s conducted mainly South-North sorties, with no signs of their attempting to fly closer to Taiwanproper,'' air force Major-General Hu Yuan-Chieh said .

He said the Russia-made Sukhois and homemade Jian-7s and Jian-8s largely flew within a zone 15-30 miles off the southeastern Chinese province of Fujian.

US Congressional delegation backs Taiwan

The leader of a visiting US Congressional delegation said on Tuesday that his group backed the call by Taiwan President Lee Teng-Hui's for China to treat Taiwan as a political equal.

``We strongly support President Lee's right to address Taipei's views of the cross-strait relationship. It is our view that the two sides should engage in a dialogue as equals,'' Republican Benjamin Gilman told mediapersons before departing.

The comments by Gilman, a Republican from New York state who chairs the House of Representatives International Relations Committee, run counter to the Clinton administration's policy.

The administration does not want to sour Washington's already fragile relationship with China and does not support Lee's call. Lee called on July 9for contact between Taiwan and China to be considered as ``special state-to-state'' ties.