diff --git a/composer.json b/composer.json
index 6752474f40a..a100313e783 100644
--- a/composer.json
+++ b/composer.json
@@ -13,7 +13,7 @@
 	],
 	"require": {
 		"php": "^7.1",
-		"guzzlehttp/guzzle": "^7.0",
+		"guzzlehttp/guzzle": "^6.0 || ^7.0",
 		"ext-json": "*"
 	},
 	"require-dev": {