FRANKFURT—Germany will push forward plans for a common corporate tax system with France in light of the recent tax overhaul in the U.S., German Chancellor Angela Merkel said, signaling her readiness to advance key European reform projects once a new German government is in place.

The comments, in Ms. Merkel’s regular weekly podcast published Saturday, come during a tense political weekend for Europe that will determine the direction of two of its biggest economies—Germany and Italy. They are the latest sign that Ms. Merkel...