German Chancellor Angela Merkel has appeared unsteady, visibly shaking while greeting the new Ukrainian leader in the hot sun in Berlin, later saying she clearly had not drunk enough water.

Key points: German Chancellor Angela Merkel said she hadn't had enough water, which caused her to shake

German Chancellor Angela Merkel said she hadn't had enough water, which caused her to shake She later told reporters she was feeling better

She later told reporters she was feeling better German media reported this is not the first time Ms Merkel has become unwell due to not drinking water

Ms Merkel's whole body visibly shook and she pursed her lips as she stood with Ukrainian President Volodymyr Zelenskiy in the 28-degree heat while a military band played their national anthems outside the chancellery.

But following the anthems, Ms Merkel seemed better, walking quickly along the red carpet with Mr Zelenskiy into the building, pausing to greet the military band and take a salute.

About an hour later, following their meeting, Ms Merkel told reporters at a joint news conference the pair had discussed bilateral issues and the Minsk peace process during Mr Zelenskiy's first visit to the German capital as president.

Ms Merkel, who turns 65 next month, smiled broadly after a reporter asked whether her shaking was cause for concern. She replied that she was fine.

"Since then I've drunk at least three glasses of water, which I apparently needed, and now I'm doing very well," she said.

She laughed and gave Mr Zelenskiy a smile when he assured reporters the Chancellor had been secure at his side.

"She was totally safe," he said.

The dpa news agency reported this was not the first time Ms Merkel had been seen shaking under similar circumstances in the hot sun.

It did not give a date for the prior incident, but said it was also ascribed to Ms Merkel not drinking enough water.

In 2014, Ms Merkel postponed a television interview at the last minute after reported weakness, but her spokesman said at the time she was able to carry it out later after eating and drinking something.

It is not publicly known if Ms Merkel, who has led Germany since 2005, has any health issues. German privacy laws are very strict on personal information.

AP