Angela Merkel has insisted she is in good health after experiencing a third bout of shaking in as many weeks at a public event in Berlin.
Video footage shows Mrs Merkel trembling, shaking back and forth alongside Finland's prime minister during a ceremony in Berlin.
"This process is clearly not finished yet but there is progress and I must live with this for a while but I am very well and you don't need to worry about me", she added.
A representative of the German government's press service said soon after the incident that Merkel was feeling fine.
A keen hiker too, Merkel herself once asserted she had a "camel-like" ability to store energy for sleepless all-night summits. "Should the chancellor tell us how she really is doing?" read a headline on the homepage of Bild, the country's largest newspaper.
Mrs Merkel was last spotted shaking as she stood alongside President Frank-Walter Steinmeier at an indoor event where Germany's new justice minister was formally appointed.
A spokesman on Wednesday dismissed any concerns over her health, saying "the chancellor is fine".
Merkel refused to answer further questions Wednesday, telling reporters who pressed the issue that "my comments on this are done today".
But she has struggled to stamp out repeated speculation that she may leave the political stage earlier than planned.
But asked by the Focus website what might be wrong this time, leading Bavarian GP Jakob Berger said the chancellor should undergo urgent health checks.
Reports in Germany say she has been seen shaking before, especially in the sun. He said shivering indicated an infection that was flaring up again.
Titled "Merkel", the film will revolve around the German leader and her decision to open Germany's borders to almost a million Syrian refugees in 2015. She is due to step down from her post when her term ends in 2021.
There were brief concerns about her well-being in 2014 when she was taken ill during a television interview. Her absences were only brief on those occasions.