diff --git a/build.xml b/build.xml
index b8de10ac66..e7ec65b8ca 100644
--- a/build.xml
+++ b/build.xml
@@ -616,6 +616,9 @@ under the License.
             <fileset dir="${basedir}/lib/ooxml">
                 <include name="xmlbeans-3.1.0.jar"/>
             </fileset>
+            <fileset dir="${basedir}/lib/main-tests">
+                <include name="mockito-core-3.2.4.jar"/>
+            </fileset>
         </delete>
 
         <condition property="jars.present">