WELLINGTON, July 14 (Xinhua) -- New Zealand's opposition party leader Todd Muller resigned on Tuesday after less than two months in the role.

"It has become clear to me that I am not the best person to be leader of the Opposition and leader of the New Zealand National Party at this critical time for New Zealand," he said in a statement.

He said the decision is "effective immediately."

"The role has taken a heavy toll on me personally, and on my family, and this has become untenable from a health perspective."

Deputy leader Nikki Kaye has been confirmed as the acting leader after Muller 's resignation, with the party holding an emergency caucus meeting Tuesday morning, local media reported.

Muller's announcement comes after the National Party was trapped by scandal of leaking private information of COVID-19 patients over the last week.

Todd Muller was elected as the leader of the New Zealand National on May 22. Nikki Kaye was elected as his deputy. They were scheduled to lead the New Zealand National Party to the general election on Sept. 19.