diff --git a/src/DynareBison.yy b/src/DynareBison.yy
index ab4f141a3513468ba25926d3d32c5b1a11dc9662..697d8bab30a882f8491e1faf2345f539802e1bf2 100644
--- a/src/DynareBison.yy
+++ b/src/DynareBison.yy
@@ -102,7 +102,7 @@ class ParsingDriver;
 %token NONLINEAR_FILTER_INITIALIZATION FILTER_ALGORITHM PROPOSAL_APPROXIMATION CUBATURE UNSCENTED MONTECARLO DISTRIBUTION_APPROXIMATION
 %token <string> NAME
 %token USE_PENALIZED_OBJECTIVE_FOR_HESSIAN INIT_STATE FAST_REALTIME RESCALE_PREDICTION_ERROR_COVARIANCE GENERATE_IRFS
-%token NAN_CONSTANT NO_STATIC NOBS NOCONSTANT NODISPLAY NOCORR NODIAGNOSTIC NOFUNCTIONS NO_HOMOTOPY VAR_MODEL_NAME
+%token NAN_CONSTANT NO_STATIC NOBS NOCONSTANT NODISPLAY NOCORR NODIAGNOSTIC NOFUNCTIONS NO_HOMOTOPY
 %token NOGRAPH POSTERIOR_NOGRAPH POSTERIOR_GRAPH NOMOMENTS NOPRINT NORMAL_PDF SAVE_DRAWS MODEL_NAME STDERR_MULTIPLES DIAGONAL_ONLY
 %token OBSERVATION_TRENDS OPTIM OPTIM_WEIGHTS ORDER OSR OSR_PARAMS MAX_DIM_COVA_GROUP ADVANCED OUTFILE OUTVARS OVERWRITE DISCOUNT
 %token PARALLEL_LOCAL_FILES PARAMETERS PARAMETER_SET PARTIAL_INFORMATION PERIODS PERIOD PLANNER_OBJECTIVE PLOT_CONDITIONAL_FORECAST PLOT_PRIORS PREFILTER PRESAMPLE
@@ -119,7 +119,7 @@ class ParsingDriver;
 %token UNIFORM_PDF UNIT_ROOT_VARS USE_DLL USEAUTOCORR GSA_SAMPLE_FILE USE_UNIVARIATE_FILTERS_IF_SINGULARITY_IS_DETECTED
 %token VALUES VAR VAREXO VAREXO_DET VARIABLE VAROBS VAREXOBS PREDETERMINED_VARIABLES VAR_EXPECTATION VAR_EXPECTATION_MODEL PLOT_SHOCK_DECOMPOSITION MODEL_LOCAL_VARIABLE
 %token WRITE_LATEX_DYNAMIC_MODEL WRITE_LATEX_STATIC_MODEL WRITE_LATEX_ORIGINAL_MODEL CROSSEQUATIONS COVARIANCE WRITE_LATEX_STEADY_STATE_MODEL
-%token XLS_SHEET XLS_RANGE LMMCP OCCBIN BANDPASS_FILTER COLORMAP VAR_MODEL PAC_MODEL QOQ YOY AOA UNDIFF PAC_EXPECTATION TREND_COMPONENT_MODEL
+%token XLS_SHEET XLS_RANGE LMMCP OCCBIN BANDPASS_FILTER COLORMAP VAR_MODEL PAC_MODEL QOQ YOY AOA PAC_EXPECTATION TREND_COMPONENT_MODEL
 %left EQUAL_EQUAL EXCLAMATION_EQUAL
 %left LESS GREATER LESS_EQUAL GREATER_EQUAL
 %left PLUS MINUS
diff --git a/src/DynareFlex.ll b/src/DynareFlex.ll
index 2bf32a9592a66a358cc621a2170ef97f3e8aa0eb..75307f2d4ad872b8e64b8e3ca584e3f7e5d44b9b 100644
--- a/src/DynareFlex.ll
+++ b/src/DynareFlex.ll
@@ -328,7 +328,6 @@ DATE -?[0-9]+([ya]|m([1-9]|1[0-2])|q[1-4]|w([1-9]{1}|[1-4][0-9]|5[0-2]))
 <DYNARE_STATEMENT>kalman_algo 	{return token::KALMAN_ALGO;}
 <DYNARE_STATEMENT>fast_kalman_filter {return token::FAST_KALMAN_FILTER;}
 <DYNARE_STATEMENT>kalman_tol 	{return token::KALMAN_TOL;}
-<DYNARE_STATEMENT>undiff     {return token::UNDIFF;}
 <DYNARE_STATEMENT>diffuse_kalman_tol 	{return token::DIFFUSE_KALMAN_TOL;}
 <DYNARE_STATEMENT>forecast 	{return token::FORECAST;}
 <DYNARE_STATEMENT>smoother 	{return token::SMOOTHER;}
@@ -349,7 +348,6 @@ DATE -?[0-9]+([ya]|m([1-9]|1[0-2])|q[1-4]|w([1-9]{1}|[1-4][0-9]|5[0-2]))
 <DYNARE_STATEMENT>optim		{return token::OPTIM;}
 <DYNARE_STATEMENT>periods	{return token::PERIODS;}
 <DYNARE_STATEMENT,DYNARE_BLOCK>model_name	{return token::MODEL_NAME;}
-<DYNARE_STATEMENT>var_model_name    {return token::VAR_MODEL_NAME;}
 <DYNARE_STATEMENT>auxiliary_model_name    {return token::AUXILIARY_MODEL_NAME;}
 <DYNARE_STATEMENT>endogenous_terminal_period 	{return token::ENDOGENOUS_TERMINAL_PERIOD;}
 <DYNARE_STATEMENT>sub_draws	{return token::SUB_DRAWS;}