diff --git a/src/libcoreint/opcodes.c b/src/libcoreint/opcodes.c
index cf8f58ced..0a20f72e2 100644
--- a/src/libcoreint/opcodes.c
+++ b/src/libcoreint/opcodes.c
@@ -45,8 +45,6 @@
  */
 
 #define OP_UNIMPLEMENTED_LIST(op) \
-    op (with)                            \
-    op (end_with)                        \
     static char __unused unimplemented_list_end
 
 #define DEFINE_UNIMPLEMENTED_OP(op) \
@@ -1402,6 +1400,68 @@ opfunc_this (opcode_t opdata, /**< operation data */
   return ret_value;
 } /* opfunc_this */
 
+/**
+ * 'With' opcode handler.
+ *
+ * See also: ECMA-262 v5, 12.10
+ *
+ * @return completion value
+ *         Returned value must be freed with ecma_free_completion_value
+ */
+ecma_completion_value_t
+opfunc_with (opcode_t opdata, /**< operation data */
+             int_data_t *int_data) /**< interpreter context */
+{
+  const idx_t expr_var_idx = opdata.data.with.expr;
+
+  int_data->pos++;
+
+  ecma_completion_value_t ret_value;
+
+  ECMA_TRY_CATCH (expr_value,
+                  get_variable_value (int_data,
+                                      expr_var_idx,
+                                      false),
+                  ret_value);
+  ECMA_TRY_CATCH (obj_expr_value,
+                  ecma_op_to_object (expr_value.value),
+                  ret_value);
+
+  ecma_object_t *obj_p = ECMA_GET_POINTER (obj_expr_value.value.value);
+
+  ecma_object_t *old_env_p = int_data->lex_env_p;
+  ecma_object_t *new_env_p = ecma_create_object_lex_env (old_env_p,
+                                                         obj_p,
+                                                         true);
+  int_data->lex_env_p = new_env_p;
+
+  ecma_completion_value_t evaluation_completion = run_int_loop (int_data);
+
+  if (evaluation_completion.type == ECMA_COMPLETION_TYPE_META)
+  {
+    opcode_t meta_opcode = read_opcode (int_data->pos);
+    JERRY_ASSERT (meta_opcode.op_idx == __op__idx_meta);
+    JERRY_ASSERT (meta_opcode.data.meta.type == OPCODE_META_TYPE_END_WITH);
+
+    int_data->pos++;
+
+    ret_value = ecma_make_empty_completion_value ();
+  }
+  else
+  {
+    ret_value = evaluation_completion;
+  }
+
+  int_data->lex_env_p = old_env_p;
+
+  ecma_deref_object (new_env_p);
+
+  ECMA_FINALIZE (obj_expr_value);
+  ECMA_FINALIZE (expr_value);
+
+  return ret_value;
+} /* opfunc_with */
+
 /**
  * Evaluate argument of typeof.
  *
@@ -1682,6 +1742,7 @@ opfunc_meta (opcode_t opdata, /**< operation data */
   switch (type)
   {
     case OPCODE_META_TYPE_VARG:
+    case OPCODE_META_TYPE_END_WITH:
     {
       return ecma_make_completion_value (ECMA_COMPLETION_TYPE_META,
                                          ecma_make_simple_value (ECMA_SIMPLE_VALUE_EMPTY),
diff --git a/src/libcoreint/opcodes.h b/src/libcoreint/opcodes.h
index 62f0412ee..b2cf22ebe 100644
--- a/src/libcoreint/opcodes.h
+++ b/src/libcoreint/opcodes.h
@@ -56,7 +56,8 @@ typedef enum
   OPCODE_META_TYPE_VARG, /**< element (var_idx) of arguments' list */
   OPCODE_META_TYPE_VARG_PROP_DATA, /**< name (lit_idx) and value (var_idx) for a data property descriptor */
   OPCODE_META_TYPE_VARG_PROP_GETTER, /**< name (lit_idx) and getter (var_idx) for an accessor property descriptor */
-  OPCODE_META_TYPE_VARG_PROP_SETTER /**< name (lit_idx) and setter (var_idx) for an accessor property descriptor */
+  OPCODE_META_TYPE_VARG_PROP_SETTER, /**< name (lit_idx) and setter (var_idx) for an accessor property descriptor */
+  OPCODE_META_TYPE_END_WITH /**< end of with statement */
 } opcode_meta_type;
 
 typedef struct
@@ -95,8 +96,7 @@ typedef struct
         p##_2 (a, delete_var, lhs, name)                                     \
         p##_3 (a, delete_prop, lhs, base, name)                              \
         p##_2 (a, typeof, lhs, obj)                                          \
-        p##_1 (a, with, expr)                                                \
-        p##_0 (a, end_with)
+        p##_1 (a, with, expr)
 
 #define OP_ASSIGNMENTS(p, a)                                                 \
         p##_3 (a, assignment, var_left, type_value_right, value_right)
diff --git a/src/libecmaobjects/ecma-helpers.c b/src/libecmaobjects/ecma-helpers.c
index 997ebb8eb..c2ec8d7cf 100644
--- a/src/libecmaobjects/ecma-helpers.c
+++ b/src/libecmaobjects/ecma-helpers.c
@@ -93,7 +93,8 @@ ecma_create_object_lex_env (ecma_object_t *outer_lexical_environment_p, /**< out
                             ecma_object_t *binding_obj_p, /**< binding object */
                             bool provide_this) /**< provideThis flag */
 {
-  JERRY_ASSERT(binding_obj_p != NULL);
+  JERRY_ASSERT(binding_obj_p != NULL
+               && !binding_obj_p->is_lexical_environment);
 
   ecma_object_t *new_lexical_environment_p = ecma_alloc_object ();
   ecma_init_gc_info (new_lexical_environment_p);
diff --git a/src/libecmaoperations/ecma-conversion.c b/src/libecmaoperations/ecma-conversion.c
index 229d8df3e..23767e5a2 100644
--- a/src/libecmaoperations/ecma-conversion.c
+++ b/src/libecmaoperations/ecma-conversion.c
@@ -391,7 +391,24 @@ ecma_op_to_string (ecma_value_t value) /**< ecma-value */
 ecma_completion_value_t
 ecma_op_to_object (ecma_value_t value) /**< ecma-value */
 {
-  JERRY_UNIMPLEMENTED_REF_UNUSED_VARS(value);
+  switch ((ecma_type_t)value.value_type)
+  {
+    case ECMA_TYPE_SIMPLE:
+    case ECMA_TYPE_NUMBER:
+    case ECMA_TYPE_STRING:
+    {
+      JERRY_UNIMPLEMENTED ();
+    }
+
+    case ECMA_TYPE_OBJECT:
+    {
+      return ecma_make_completion_value (ECMA_COMPLETION_TYPE_NORMAL,
+                                         ecma_copy_value (value, true),
+                                         ECMA_TARGET_ID_RESERVED);
+    }
+  }
+
+  JERRY_UNREACHABLE ();
 } /* ecma_op_to_object */
 
 /**
diff --git a/src/libecmaoperations/ecma-exceptions.c b/src/libecmaoperations/ecma-exceptions.c
index 2377f945c..7ca4802c3 100644
--- a/src/libecmaoperations/ecma-exceptions.c
+++ b/src/libecmaoperations/ecma-exceptions.c
@@ -36,6 +36,9 @@
 ecma_object_t*
 ecma_new_standard_error (ecma_standard_error_t error_type) /**< native error type */
 {
+  /* SyntaxError should be treated as an early error */
+  JERRY_ASSERT (error_type != ECMA_ERROR_SYNTAX);
+
   JERRY_UNIMPLEMENTED_REF_UNUSED_VARS(error_type);
 } /* ecma_new_standard_error */
 
diff --git a/src/libjsparser/parser.c b/src/libjsparser/parser.c
index d22bd8115..878e0f925 100644
--- a/src/libjsparser/parser.c
+++ b/src/libjsparser/parser.c
@@ -2083,7 +2083,7 @@ parse_with_statement (void)
   skip_newlines ();
   parse_statement ();
 
-  DUMP_VOID_OPCODE (end_with);
+  DUMP_OPCODE_3 (meta, OPCODE_META_TYPE_END_WITH, INVALID_VALUE, INVALID_VALUE);
 }
 
 /* switch_statement
diff --git a/src/liboptimizer/pretty-printer.c b/src/liboptimizer/pretty-printer.c
index 97b840e15..f5206c8e2 100644
--- a/src/liboptimizer/pretty-printer.c
+++ b/src/liboptimizer/pretty-printer.c
@@ -347,8 +347,7 @@ pp_opcode (opcode_counter_t oc, opcode_t opcode, bool is_rewrite)
   uint8_t opcode_num = opcode.op_idx;
 
   __printf ("%3d: %20s ", oc, opcode_names[opcode_num]);
-  if (opcode_num != NAME_TO_ID (nop) && opcode_num != NAME_TO_ID (ret)
-      && opcode_num != NAME_TO_ID (end_with))
+  if (opcode_num != NAME_TO_ID (nop) && opcode_num != NAME_TO_ID (ret))
   {
     for (i = 1; i < opcode_sizes[opcode_num]; i++)
     {
@@ -415,7 +414,6 @@ pp_opcode (opcode_counter_t oc, opcode_t opcode, bool is_rewrite)
     CASE_EXIT (exitval, "exit", status_code)
     CASE_SINGLE_ADDRESS (retval, "return", ret_value)
     CASE_ZERO_ADDRESS (ret, "return")
-    CASE_ZERO_ADDRESS (end_with, "")
     CASE_ZERO_ADDRESS (nop, "")
     TODO (Refine to match new opcodes)
     CASE_VARG_1_LHS (array_decl, lhs, "=", "[", list, "]")
diff --git a/tests/unit/common.h b/tests/unit/common.h
index 38e0d1f56..70763d9ae 100644
--- a/tests/unit/common.h
+++ b/tests/unit/common.h
@@ -38,8 +38,7 @@ opcodes_equal (const opcode_t *opcodes1, opcode_t *opcodes2, uint16_t size)
       if (opcode_num1 != opcode_num2)
         return false;
 
-      if (opcode_num1 == NAME_TO_ID (nop) || opcode_num1 == NAME_TO_ID (ret)
-          || opcode_num1 == NAME_TO_ID (end_with))
+      if (opcode_num1 == NAME_TO_ID (nop) || opcode_num1 == NAME_TO_ID (ret))
         return true;
 
       for (j = 1; j < opcode_sizes[opcode_num1]; j++)
@@ -50,4 +49,4 @@ opcodes_equal (const opcode_t *opcodes1, opcode_t *opcodes2, uint16_t size)
   return true;
 }
 
-#endif // COMMON_H
\ No newline at end of file
+#endif // COMMON_H