Since Mr Seehofer had called Mr Westerwelle a crybaby just weeks earlier, it was a touching reconciliation.

ECONOMIST: The complex etiquette of du and Sie in Germany

The latest attempt at reconciliation a modest tax-relief deal between the CDU and FDP backfired because the CSU's chief, Horst Seehofer felt ignored.

ECONOMIST: Why Germany is so reluctant to stump up for the euro

Ms Merkel will look to Mr zu Guttenberg for an electoral lift, but he is beholden to Mr Seehofer, who has been one of her main tormentors since taking over Bavaria in October.

ECONOMIST: A German government shuffle