Luxembourg Prime Minister Xavier Bettel was hospitalised Sunday and will be kept under observation as tests are carried out a week after he tested positive for Covid-19, the government said.
Bettel, 48, is to stay in hospital for 24 hours as a precautionary measure, the statement said.
He began 10 days of self isolation on June 27, less than two days after attending a European Union summit in Brussels, but none of the other 26 EU leaders who attended the summit were considered a contact case.
The Luxembourg premier had already received one dose of the AstraZeneca covid vaccine on May 6.
The country of 630,000 inhabitants has seen a surge of infections in the past 10 days, and 136 people tested positive for the coronavirus on Saturday, a level last seen in Luxembourg in mid-May.