diff --git a/backend/app/plugins/wiaas/includes/class-wiaas-cart.php b/backend/app/plugins/wiaas/includes/class-wiaas-cart.php
index d057b15..df8c358 100644
--- a/backend/app/plugins/wiaas/includes/class-wiaas-cart.php
+++ b/backend/app/plugins/wiaas/includes/class-wiaas-cart.php
@@ -164,11 +164,35 @@ class Wiaas_Cart {
 				return false;
 			}
 
-			// TODO: Add validation that only packages from the same country can be added to cart at the same time
-			update_user_meta( get_current_user_id(), '_wiaas_cart_items_country', $country);
+			// Validate that order contains only stuff from single commercial lead / reseller / shop owner
+			if ( ! WC()->cart->is_empty() ) {
 
-			// TODO: Add validation that only packages from the same shop can be added to cart at the same time
-			update_user_meta( get_current_user_id(), '_wiaas_cart_shop_owner_id', $shop_owner_id);
+				$current_shop_owner_id = get_user_meta(get_current_user_id(), '_wiaas_cart_shop_owner_id', true);
+
+				if (absint($shop_owner_id) !== absint($current_shop_owner_id)) {
+
+					wc_add_notice('Only packages from one catalogue can be purchased at the same time!', 'error');
+					return false;
+				}
+			} else {
+
+				update_user_meta( get_current_user_id(), '_wiaas_cart_shop_owner_id', $shop_owner_id);
+			}
+
+			// Validate that order contains only items for single country
+			if ( ! WC()->cart->is_empty() ) {
+
+				$current_country = get_user_meta(get_current_user_id(), '_wiaas_cart_items_country', true);
+
+				if ($country !== $current_country) {
+
+					wc_add_notice('Only packages from one country can be purchased at the same time!', 'error');
+					return false;
+				}
+			} else {
+
+				update_user_meta( get_current_user_id(), '_wiaas_cart_items_country', $country);
+			}
 
             $customer_id = wiaas_get_current_user_organization_id();