国际英语新闻：President Koehler's resignation brings shock to Germany

Koehler's departure came at a time when Merkel's government is already facing sinking popularity for failing to act quickly enough to control a euro zone debt crisis and constant internal disputes within the ruling coalition.

Less than a week ago, Roland Koch, a ex-rival to Merkel but an influential politician in conservative bloc, resigned as premier of the state of Hesse, a move deemed as another blow to Merkel's ruling coalition.

To make things worse, Koehler triggered widespread criticism in a May 22 radio interview which suggested that German military action abroad also served economic interests.

He was quoted as saying in the interview that a country like Germany with a heavy reliance on foreign trade "must also understand that in certain cases, in an emergency, military operations are necessary to protect our interests." He cited as examples maintaining free trade routes and preventing regional instability that could have a negative impact on Germany's trade, jobs and income.

Opposition politicians have accused Koehler of "gunboat diplomacy." Koehler, however, stressed later that he had been misunderstood.

On Monday while announcing his quit, Koehler also expressed anger at some critics which suggested he supported "German military missions that are not covered by the constitution."

"This criticism is devoid of any justification. It also is lacking in the necessary respect for the presidential office," he said.

German media comments on Monday showed widespread incomprehension over Koehler's shock resignation and criticized him for overreacting.

"The President quits and leaves the people behind at a loss," commented the German weekly Die Zeit. "In midst of a severe economic crisis, at a time when the federal government is shaky, he starts a crisis at the top."

It is the first time in Germany's postwar history that a federal president has resigned. According to the German constitution, the head of the Bundesrat, the upper house of parliament that represents Germany's federal states, will take over as interim head of state. In the current situation, Jens Boehrnsen, the Social Democratic (SPD) mayor of Bremen, will take over.

A special Federal Convention, made up of all members of federal parliament and an equal number of delegates from the 16 state parliaments, must elect the next German president within 30 days.