German President and key Merkel-ally Christian Wulff has resigned today after prosecutors sought to strip him of his immunity over a dodgy loans case, the BBC reports.

Wulff's resignation came after a series of scandals.

The situation came to a head last year when German newspaper Bild reported that Wulf lied to a regional parliament in 2010 when he said he had no business ties to an entrepreneur,  Egon Geerkens, with whom he had spent his 2009 Christmas vacation.

In fact, the paper reported that Wulff had previously received a 500,000 euro ($648,800) loan from the businessman's wife at a rate below the usual bank rate.

Publicly, Wulff claimed that the loan was a personal loan, but behind the scenes he had threatened the editor of Bild,  Kai Diekmann, saying that there would be "war" if the article was published. Bild published details of these threats, leading to numerous calls for Wulff to resign.