"We understand that the National Security Bureau must possess certain information and as an opposition party we can't really do anything if the ruling party uses national resources against us," Su said.
Su declined to say whether the private meeting was arranged by AIT or the KMT.
At a separate setting yesterday, Chen dismissed the allegations that the DPP would resort to staging incidents to increase cross-strait tensions to influence the March poll.
"What's a `dirty trick?' Who said [I would resort to `dirty tricks']? Who knows what Burghardt said [to Siew]? You [reporters] shouldn't ask me to comment on rumors," the president said when approached by reporters for comment on an Apple Daily report yesterday.
Chen doubles as DPP chairman.
The paper published what it said were minutes from the Siew-Burghardt meeting.
AIT Spokesman Thomas Hodges yesterday said he could not confirm the authenticity of the minutes because he had not read the Apple Daily report.
Hodges said his office might issue a statement on Monday after reading the report.
"The US government has no favorite in the 2008 presidential election. We will work with whichever president is selected by the Taiwan people," he said when asked by the Taipei Times for comment on the minutes, which seemed to suggest the US favored the KMT.
AIT acting spokesman Lawrence Walker said the AIT had "no comment" on whether his office had contacted the KMT yesterday requesting an explanation after the Apple Daily report.
Meanwhile, Hsieh yesterday said he believed the minutes had been leaked by the KMT.
The KMT shouldn't accuse Chen and the DPP of planning "dirty tricks" without providing evidence, Hsieh said.
Hsieh also urged Ma to stop speaking poorly of Taiwan to foreigners.
Foreigners "will not give Taiwan more international room if we keep telling them bad things about Taiwan."
"Ma always says bad things about Taiwan when he is abroad," Hsieh said.
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