Yeo said in parliament that the revelations by the whistle-blower website had been "disastrous" for US diplomacy.Singaporean leaders were left red-faced after documents released by WikiLeaks last December detailed the city-state's top diplomats bad-mouthing regional neighbours to US diplomats in private exchanges.
Washington has condemned the release of masses of confidential commentary by its diplomats around the world and has tried to placate a number of countries that felt offended.
"Would it affect communications with US diplomats? I think inevitably, because it has happened once, it can happen again and then we got to be more careful," Yeo said in response to a query from a fellow member of parliament.
"So, yes we've to be more guarded in our communication with US diplomats."
Yeo added: "It is a loss because I think part of human relationship is that we must be able to share more when we trust somebody more."
However, Yeo said there were "significant inaccuracies" in the reports of some leaked cables, particularly those released by Australia's Fairfax media group in December.
"It's not even first-hand and the original leaks have not been released, so I think it's not wise for us to go into details," he said.
In separate remarks in parliament today, Singaporean Home Affairs Minister K Shanmugam warned that the government would not tolerate information leaks in a similar vein to the WikiLeaks saga.
"We believe that everyone involved in a leak of information, whether in government or outside, should be dealt with firmly. We do not intend to encourage cat and mouse games," he said.
"Public interest in free flow of information cannot justify the abuse of confidential government information."
The Fairfax reports of the WikiLeaks documents detailed Australian and US diplomats talking about Singaporean leaders' perception of close Asian allies as being "corrupt and incompetent," with neighbour Malaysia taking the brunt of the criticism.
The episode led to Malaysian Foreign Minister Anifah Aman summoning the Singaporean ambassador in Kuala Lumpur, where he handed over a protest note and expressed "Malaysia's deep concern and displeasure over the comments"