Canadian Prime Minister Justin Trudeau said he tested negative for COVID-19 last month after experiencing a sore throat.

“Earlier in September, I had a bit of a throat tickle,” Trudeau said Monday in Ottawa, responding to a reporter’s question. “I got tested. It was negative and I went back to work a few days later when the doctor told me I was clear to do so.”

The Canadian leader said he wasn’t tested in March when his wife, Sophie Gregoire Trudeau, was diagnosed with COVID-19 because he was asymptomatic. Instead, he chose to self-isolate for 14 days, following the public health advice at the time. “Throughout I’ve listened to the advice of medical professionals and public health every step of the way,” he said.

The health of Canada’s political leaders is coming under closer scrutiny after U.S. President Donald Trump tested positive for the virus last week, along with First Lady Melania Trump, at least two White House aides who travel with the president and three Republican senators. Trudeau’s main political rival has also tested positive.

Trudeau gave a press conference to address growing concern about the recent spike of COVID-19 cases. Officials in two of the country’s largest provinces are tightening restrictions to deal with the outbreaks.

Trudeau said case numbers in Canada are going “in the wrong direction” after a summer lull. Health authorities are currently reporting 166,156 cases, including 9,481 deaths.