BERLIN — Chancellor Angela Merkel of Germany insisted on Wednesday that she was “well” and capable of fulfilling her job after she was seen shaking uncontrollably in public for the third time in less than a month, reviving concern about her health.

In videos of the event, she was seen struggling to remain still as her arms and legs began trembling while she stood beside Antti Rinne, the prime minister of Finland, watching a military honor guard.

As she had in the previous incidents, Ms. Merkel clasped her hands in front of her in an apparently futile attempt to contain the tremors.

Speaking to reporters less than an hour later during a news briefing, Ms. Merkel said, “I am well.”

Pressed by a reporter for more of an explanation, Ms. Merkel said that the shaking on Wednesday was part of the psychological trauma she suffered after experiencing uncontrolled trembling under similar circumstances on June 18, while appearing with President Volodymyr Zelensky of Ukraine in the full afternoon sun.