Israeli Defense Minister Ehud Barak is quitting politics.

In a surprise move Monday, Mr. Barak announced he will not run in the country's January elections, but will stay in his post until a new government is formed.

The 70-year-old former prime minister said he has “exhausted dealing with political life” and wants to spend more time with his family. He also said he wants to make room for others to serve in leadership positions.

Prime Minister Benjamin Netanyahu said he respects Mr. Barak's decision and appreciates the defense minister's contributions to state security.

Mr. Barak founded the center-left Independence party after splitting from the Labor party in 2011.

He became a close ally of Mr. Netanyahu in recent years, but their relationship has become strained by differences in how to seek U.S. support for Israel's strategy toward Iran.

In the opinion of Hamas, Mr. Barak's resignation is an admission of failure in the latest Israeli military operations.

Hamas' Prime Minister Ismail Haniyeh said the announcement reflects the military and political failures of Israel's eight-day aerial bombardment of the Gaza Strip.