diff --git a/config/external/icu/data/icudt78l.dat b/config/external/icu/data/icudt78l.dat
index b61e7c1ae23b..8b867929c43b 100644
Binary files a/config/external/icu/data/icudt78l.dat and b/config/external/icu/data/icudt78l.dat differ
diff --git a/intl/icu/source/data/zone/en_GB.txt b/intl/icu/source/data/zone/en_GB.txt
index aa9880b27d32..5d83862a24e3 100644
--- a/intl/icu/source/data/zone/en_GB.txt
+++ b/intl/icu/source/data/zone/en_GB.txt
@@ -7,4 +7,5 @@ en_GB{
         "Europe:London"{
             sd{"BST"}
+            ss{"GMT"}
         }
         "meta:Europe_Central"{