BERLIN — On Feb. 18, Germany did something unthinkable. It voted in favor of a U.N. Security Council resolution calling the Israeli settlements in occupied Palestinian territory illegal and demanding the immediate halt of all settlement activity.

The resolution did not pass — the United States, the only one of the Security Council’s 15 members to vote against it, vetoed it. That did not stop the German vote from opening a serious rift between Germany and Israel.

Ruprecht Polenz, a conservative lawmaker and chairman of the German Parliament’s Foreign Affairs Committee, said “the vote was highly unusual” given Germany’s practice of abstaining from or voting against any U.N. resolutions criticizing Israel.

But Mr. Polenz was adamant that it did not mean that Germany no longer defended the security of Israel. “It means that Chancellor Angela Merkel is trying to explain to the Israeli government that with the extraordinary changes taking place across the Middle East, time is not on its side when it comes to resolving the conflict with the Palestinians,” he said.