As part of the Merkel cabinet, he supported the Magna deal under protest, arguing that insolvency arrangements might best determine the value of Opel.

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Mr Guttenberg, a baron, was one of the most popular ministers in Chancellor Angela Merkel's cabinet and tipped by some as a future German leader.

BBC: Germany's Guttenberg 'deliberately' plagiarised

The U.S. dollar index was down 0.46% to 75.095. (Read Greek Cabinet Shaken Up, Sarkozy And Merkel Call For Debt Solution By July).

FORBES: Oil, Dollar Fall Amid Greek Crisis And Global Slowdown