Benjamin Netanyahu has been rushed to hospital after complaining of chest pains.
The Israeli prime minister, 73, is undergoing tests but is otherwise in a “good condition”, officials said.
A “preliminary assessment” by doctors suggests he is suffering from dehydration and nothing “out of order” has been found so far, his office said in a statement.
Footage later aired by Israeli TV showed Netanyahu in hospital smiling and urging the public to take care during the hot weather.
He said: “Thank God, I feel really well. I ask you all, spend less time in the sun less, drink more water, and may we all have a good new week.”
The Israeli PM was previously taken to hospital with chest pains in October 2022, but was later discharged after test results came back normal.
He also underwent a “routine colonoscopy” in January earlier this year.
Local reports said the Israeli leader reported feeling unwell at his home in Caesarea, where he had been spending the weekend, and was taken to hospital from there.
He was fully conscious en route to Sheba hospital, in Tel Hashomer, near Tel Aviv, according to local reports.
Israel’s Channel 12 TV said he was not undergoing sedation and no procedures were underway to declare him incapacitated.
A spokesperson for his office confirmed: “Prime Minister Netanyahu arrived a short while ago to the Sheba Medical Center.
“He is well and is undergoing a medical evaluation.”