"One who brings peace between people is not a liar, he says something good, or reports something good."  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ لَيْسَ بِالْكَاذِبِ مَنْ أَصْلَحَ بَيْنَ النَّاسِ فَقَالَ خَيْرًا أَوْ نَمَى خَيْرًا  

"it is not lawful to lie except in three cases: Something the man tells his wife to please her, to lie during war, and to lie in order to bring peace between the people."  

قَالَ رَسُولُ اللَّهِ ﷺ لاَ يَحِلُّ الْكَذِبُ إِلاَّ فِي ثَلاَثٍ يُحَدِّثُ الرَّجُلُ امْرَأَتَهُ لِيُرْضِيَهَا وَالْكَذِبُ فِي الْحَرْبِ وَالْكَذِبُ لِيُصْلِحَ بَيْنَ النَّاسِ وَقَالَ مَحْمُودٌ فِي حَدِيثِهِ لاَ يَصْلُحُ الْكَذِبُ إِلاَّ فِي ثَلاَثٍ