diff --git a/packages/components/CHANGELOG.md b/packages/components/CHANGELOG.md
index 79b6acdd2e573e..ccafd5b79f0c0d 100644
--- a/packages/components/CHANGELOG.md
+++ b/packages/components/CHANGELOG.md
@@ -18,6 +18,7 @@
 ### Enhancements
 
 -   `PaletteEdit`: use `Item` internally instead of custom styles ([#66164](https://github.com/WordPress/gutenberg/pull/66164)).
+-   `Popover`: Use small size variant for close button when `expandOnMobile` prop is enabled ([#66587](https://github.com/WordPress/gutenberg/pull/66587)).
 
 ### Experimental
 
diff --git a/packages/components/src/popover/index.tsx b/packages/components/src/popover/index.tsx
index 3005f13c952ec0..1b7fb31539c6d0 100644
--- a/packages/components/src/popover/index.tsx
+++ b/packages/components/src/popover/index.tsx
@@ -419,6 +419,7 @@ const UnforwardedPopover = (
 					</span>
 					<Button
 						className="components-popover__close"
+						size="small"
 						icon={ close }
 						onClick={ onClose }
 					/>