Burma's pro-democracy leader Aung San Suu Kyi was forced to call a halt to a news conference in the Swiss capital Bern after being taken ill.

The Nobel peace prize winner said she felt exhausted after the long trip to Europe and appeared to bend over in pain before vomiting. "I'm so sorry," she said, before being escorted out by her aide and officials.

She has been on a historic 17-day trip, almost a quarter of a century since she left Europe for a military-controlled Burma and where she subsequently spent the majority of the next 22 years under house arrest.

The 66-year-old is now a member of the Burmese parliament and is due to visit Britain, France, Ireland and Norway in a tour that she hopes will strengthen international involvement in reform in Burma.

She was met with a standing ovation in an earlier speech to the United Nations in Geneva and said she did "not stand here as a representative of the workers, or of employers, or of government."

In a personal admission to the packed audience, she said: "I don't understand why people say that I am full of courage. I feel terribly nervous."