diff --git a/src/cfg.c b/src/cfg.c
index 6f3cbfef..fd8a7118 100644
--- a/src/cfg.c
+++ b/src/cfg.c
@@ -207,6 +207,8 @@ int uvg_config_init(uvg_config *cfg)
 
   cfg->lfnst = false;
 
+  cfg->isp = false;
+
   parse_qp_map(cfg, 0);
 
   cfg->jccr = 0;
@@ -1450,6 +1452,9 @@ int uvg_config_parse(uvg_config *cfg, const char *name, const char *value)
   else if OPT("lfnst") {
     cfg->lfnst = atobool(value);
   }
+  else if OPT("isp") {
+    cfg->isp = atobool(value);
+  }
   else if OPT("jccr") {
     cfg->jccr = (bool)atobool(value);
   }
diff --git a/src/cli.c b/src/cli.c
index 53f2df9b..8beb1b0f 100644
--- a/src/cli.c
+++ b/src/cli.c
@@ -178,6 +178,8 @@ static const struct option long_options[] = {
   { "no-mip",                   no_argument, NULL, 0 },
   { "lfnst",                    no_argument, NULL, 0 },
   { "no-lfnst",                 no_argument, NULL, 0 },
+  { "isp",                      no_argument, NULL, 0 },
+  { "no-isp",                   no_argument, NULL, 0 },
   { "jccr",                     no_argument, NULL, 0 },
   { "no-jccr",                  no_argument, NULL, 0 },
   { "amvr",                     no_argument, NULL, 0 },
@@ -662,6 +664,7 @@ void print_help(void)
     "      --(no-)mip             : Enable matrix weighted intra prediction.\n"
     "      --(no-)lfnst           : Enable low frequency non-separable transform.\n"
     "                                 [disabled]\n"
+    "      --(no-)isp             : Enable intra sub partitions. [disabled]\n"
     "      --mts <string>         : Multiple Transform Selection [off].\n"
     "                               (Currently only implemented for intra\n"
     "                               and has effect only when rd >= 2)\n"
diff --git a/src/uvg266.h b/src/uvg266.h
index 1801c8ac..5a6a27aa 100644
--- a/src/uvg266.h
+++ b/src/uvg266.h
@@ -526,6 +526,8 @@ typedef struct uvg_config
   /** \brief enable low frequency non-separable transform */
   int8_t lfnst;
 
+  /** \brief enable intra sub partitions*/
+  int8_t isp;
 
   int8_t jccr;