diff --git a/includes/class-wc-discounts.php b/includes/class-wc-discounts.php
index d8091211fe9..e82dad60546 100644
--- a/includes/class-wc-discounts.php
+++ b/includes/class-wc-discounts.php
@@ -52,6 +52,18 @@ class WC_Discounts {
 		}
 	}
 
+	/**
+	 * Set items directly. Used by WC_Cart_Totals.
+	 *
+	 * @since 3.2.3
+	 * @param array $items Items to set.
+	 */
+	public function set_items( $items ) {
+		$this->items     = $items;
+		$this->discounts = array();
+		uasort( $this->items, array( $this, 'sort_by_price' ) );
+	}
+
 	/**
 	 * Normalise cart items which will be discounted.
 	 *