diff --git a/src/plugins/postcss-icss-parser.js b/src/plugins/postcss-icss-parser.js
index 1cb7a988..6730f50b 100644
--- a/src/plugins/postcss-icss-parser.js
+++ b/src/plugins/postcss-icss-parser.js
@@ -75,8 +75,12 @@ export default postcss.plugin(
 
       // Replace tokens in at-rules
       css.walkAtRules((atrule) => {
-        // eslint-disable-next-line no-param-reassign
-        atrule.params = replaceImportsInString(atrule.params.toString());
+        // Due reusing `ast` from `postcss-loader` some plugins may lack
+        // `params` property, we need to account for this possibility
+        if (atrule.params) {
+          // eslint-disable-next-line no-param-reassign
+          atrule.params = replaceImportsInString(atrule.params.toString());
+        }
       });
 
       // Replace tokens in export