diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -5881,9 +5881,11 @@
 static _PyUnicode_Name_CAPI *ucnhash_CAPI = NULL;
 
 PyObject *
-PyUnicode_DecodeUnicodeEscape(const char *s,
-                              Py_ssize_t size,
-                              const char *errors)
+_PyUnicode_DecodeUnicodeEscape(const char *s,
+                               Py_ssize_t size,
+                               const char *errors,
+                               char *first_invalid_escape_char,
+                               Py_ssize_t *first_invalid_escape_idx)
 {
     const char *starts = s;
     _PyUnicodeWriter writer;
@@ -5891,6 +5893,9 @@
     PyObject *errorHandler = NULL;
     PyObject *exc = NULL;
 
+    // so we can remember if we've seen an invalid escape char or not
+    *first_invalid_escape_idx = -1;
+
     if (size == 0) {
         _Py_RETURN_UNICODE_EMPTY();
     }
@@ -6065,9 +6070,10 @@
             goto error;
 
         default:
-            if (PyErr_WarnFormat(PyExc_DeprecationWarning, 1,
-                                 "invalid escape sequence '\\%c'", c) < 0)
-                goto onError;
+            if (*first_invalid_escape_idx == -1) {
+                *first_invalid_escape_idx = s - starts;
+                *first_invalid_escape_char = c;
+            }
             WRITE_ASCII_CHAR('\\');
             WRITE_CHAR(c);
             continue;
@@ -6102,6 +6108,26 @@
     return NULL;
 }
 
+PyObject *
+PyUnicode_DecodeUnicodeEscape(const char *s,
+                              Py_ssize_t size,
+                              const char *errors)
+{
+    char first_invalid_escape_char;
+    Py_ssize_t first_invalid_escape_idx;
+    PyObject *result = _PyUnicode_DecodeUnicodeEscape(s, size, errors, &first_invalid_escape_char, &first_invalid_escape_idx);
+    if (result == NULL)
+        return NULL;
+    if (first_invalid_escape_idx != -1) {
+        if (PyErr_WarnFormat(PyExc_DeprecationWarning, 1,
+                             "invalid escape sequence '\\%c'", first_invalid_escape_char) < 0) {
+            Py_DECREF(result);
+            return NULL;
+        }
+    }
+    return result;
+}
+
 /* Return a Unicode-Escape string version of the Unicode object.
 
    If quotes is true, the string is enclosed in u"" or u'' quotes as
diff --git a/Python/ast.c b/Python/ast.c
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -4116,8 +4116,15 @@
     return PyUnicode_DecodeUTF8(t, s - t, NULL);
 }
 
+PyObject *
+_PyUnicode_DecodeUnicodeEscape(const char *s,
+                               Py_ssize_t size,
+                               const char *errors,
+                               char *first_invalid_escape_char,
+                               Py_ssize_t *first_invalid_escape_idx);
+
 static PyObject *
-decode_unicode_with_escapes(struct compiling *c, const char *s, size_t len)
+decode_unicode_with_escapes(struct compiling *c, const node *n, const char *s, size_t len)
 {
     PyObject *v, *u;
     char *buf;
@@ -4170,8 +4177,20 @@
     len = p - buf;
     s = buf;
 
-    v = PyUnicode_DecodeUnicodeEscape(s, len, NULL);
+    char first_invalid_escape_char;
+    Py_ssize_t first_invalid_escape_idx;
+    v = _PyUnicode_DecodeUnicodeEscape(s, len, NULL, &first_invalid_escape_char, &first_invalid_escape_idx);
     Py_XDECREF(u);
+
+    if (v != NULL && first_invalid_escape_idx != -1) {
+        Py_DECREF(v);
+        char buf[300];
+        PyOS_snprintf(buf, sizeof(buf),
+                      "invalid escape sequence \\%c",
+                      first_invalid_escape_char);
+        ast_error(c, n, buf);
+		return NULL;
+    }
     return v;
 }
 
@@ -4313,7 +4332,7 @@
                                                     literal_end-literal_start,
                                                     NULL, NULL);
         else
-            *literal = decode_unicode_with_escapes(c, literal_start,
+            *literal = decode_unicode_with_escapes(c, n, literal_start,
                                                    literal_end-literal_start);
         if (!*literal)
             return -1;
@@ -5056,7 +5075,7 @@
         if (*rawmode)
             *result = PyUnicode_DecodeUTF8Stateful(s, len, NULL, NULL);
         else
-            *result = decode_unicode_with_escapes(c, s, len);
+            *result = decode_unicode_with_escapes(c, n, s, len);
     }
     return *result == NULL ? -1 : 0;
 }