"I am riding to the Jews tomorrow. Do not initiate the greeting with them, and if they greet you, then say: Wa 'alaikum (and also upon you)". (Using translation from Ibn Mājah 3699)
قَالَ رَسُولُ اللهِ ﷺ إِنَّا غَادُونَ عَلَى يَهُودَ فَلَا تَبْدَءُوهُمْ بِالسَّلَامِ فَإِذَا سَلَّمُوا عَلَيْكُمْ فَقُولُوا وَعَلَيْكُمْ