Before that Steinmeier was called as the main adversary of Merkel on her way to the 4th term of being a Chancellor. Angela Merkel supports Steinmeier by all means. She has already called him as a right candidate and noted that it's a signal of stability at unstable times. Although Steinmeier is a member of the Social-Democratic party withing the ruling Merkel's coalition, he doesn't agree with the Chancellor on a range of international issues. Thus, the Minister demonstrates his readiness for a dialogue with Russia, while Merkel has taken quite a tough stance. In Germany Steinmeier is criticized for his allegedly excessive 'pro-Russian' stance.
Thus, experts believe that Merkel eliminated the adversary, having nominated him and can now easily run for the 4th term despite advocating liberal values and 'change of power'. The German presidential elections will take place in March next year. Unlike a chancellor, a president has just ceremonial functions.