Merkel, 64, has no history of serious health issues
Nahles was a critical part in forging and keeping alive the grand coalition
US forces are set to soon withdraw after President Donald Trump in December announced the pullout of around 2,000 troops
Shortly after takeoff from Berlin on Thursday, Merkel's Airbus A340-300 was forced to turn back over Dutch airspace and make an emergency landing in Cologne
An enormously popular leader at her peak, in recent state elections it became all too clear that Merkel had become an electoral liability for her party
Merkel, 64, will stagger her political exit by first giving up the leadership job of her Christian Democratic Union in December
Merkel's favoured successor is CDU party secretary general Annegret Kramp-Karrenbauer
German local elections highlight EU's existential problem
Merkel and Erdogan are attempting to ease tension after Erdogan last year accused German officials of using Nazi methods to stop his officials from campaigning
Adding that "it would be best if we could be exempted" from the tariffs.
The German chancellor also said multilateralism is under threat and protectionism is not the answer to the world's problems
Investors are bracing for the outcome, with the euro forecast to drop if the SPD bows out.
The next hurdles are a key vote by her reluctant SPD partners later this month and then finalising the deal in another round of talks
Earlier, Merkel had said that the talks would be "tough" but that she was hopeful that the parties would conclude the preliminary round by Friday
Merkel's conservative Union bloc and the Social Democrats have run Germany together for the past four years
The historic echoes reflect Merkel's tarnished election victory and Germany's slipped halo as Europe's anchor of liberal stability
Europe needs a strong Germany, it is desirable to get a government in place quickly, Merkel told
Germany enters political no-man's land
Merkel has been trying to cobble together a coalition among her Christian Democratic Union, its Bavarian wing (the Christian Social Union), the FDP and the Greens
Germany funds foundations for its political parties. If the far right gets one, we're one step closer to globalizing the alt-right