diff --git a/packages/block-library/src/rss/index.php b/packages/block-library/src/rss/index.php
index dc25ac97780067..922db4c7aed759 100644
--- a/packages/block-library/src/rss/index.php
+++ b/packages/block-library/src/rss/index.php
@@ -92,6 +92,10 @@ function render_block_core_rss( $attributes ) {
 	if ( isset( $attributes['columns'] ) && 'grid' === $attributes['blockLayout'] ) {
 		$class .= ' columns-' . $attributes['columns'];
 	}
+
+	if ( isset( $attributes['className'] ) ) {
+		$class .= ' ' . $attributes['className'];
+	}
 	
 	$list_items_markup = "<ul class='{$class}'>{$list_items}</ul>";
 
diff --git a/packages/block-library/src/search/index.php b/packages/block-library/src/search/index.php
index 2589d360ef56c4..e7f4e3ef013bee 100644
--- a/packages/block-library/src/search/index.php
+++ b/packages/block-library/src/search/index.php
@@ -44,6 +44,10 @@ function render_block_core_search( $attributes ) {
 		$class .= ' ' . $attributes['className'];
 	}
 
+	if ( isset( $attributes['align'] ) ) {
+		$class .= ' align' . $attributes['align'];
+	}
+
 	return sprintf(
 		'<form class="%s" role="search" method="get" action="%s">%s</form>',
 		$class,