diff --git a/ip/link_gre.c b/ip/link_gre.c
index bc1cee8f..ede761b2 100644
--- a/ip/link_gre.c
+++ b/ip/link_gre.c
@@ -31,9 +31,9 @@ static void gre_print_help(struct link_util *lu, int argc, char **argv, FILE *f)
 	);
 	fprintf(f,
 		"                     [ local ADDR ]\n"
-		"                     [ [i|o]seq ]\n"
-		"                     [ [i|o]key KEY ]\n"
-		"                     [ [i|o]csum ]\n"
+		"                     [ [no][i|o]seq ]\n"
+		"                     [ [i|o]key KEY | no[i|o]key ]\n"
+		"                     [ [no][i|o]csum ]\n"
 		"                     [ ttl TTL ]\n"
 		"                     [ tos TOS ]\n"
 		"                     [ [no]pmtudisc ]\n"
@@ -210,28 +210,52 @@ get_failed:
 			iflags |= GRE_KEY;
 			oflags |= GRE_KEY;
 			ikey = okey = tnl_parse_key("key", *argv);
+		} else if (!matches(*argv, "nokey")) {
+			iflags &= ~GRE_KEY;
+			oflags &= ~GRE_KEY;
+			ikey = okey = 0;
 		} else if (!matches(*argv, "ikey")) {
 			NEXT_ARG();
 			iflags |= GRE_KEY;
 			ikey = tnl_parse_key("ikey", *argv);
+		} else if (!matches(*argv, "noikey")) {
+			iflags &= ~GRE_KEY;
+			ikey = 0;
 		} else if (!matches(*argv, "okey")) {
 			NEXT_ARG();
 			oflags |= GRE_KEY;
 			okey = tnl_parse_key("okey", *argv);
+		} else if (!matches(*argv, "nookey")) {
+			oflags &= ~GRE_KEY;
+			okey = 0;
 		} else if (!matches(*argv, "seq")) {
 			iflags |= GRE_SEQ;
 			oflags |= GRE_SEQ;
+		} else if (!matches(*argv, "noseq")) {
+			iflags &= ~GRE_SEQ;
+			oflags &= ~GRE_SEQ;
 		} else if (!matches(*argv, "iseq")) {
 			iflags |= GRE_SEQ;
+		} else if (!matches(*argv, "noiseq")) {
+			iflags &= ~GRE_SEQ;
 		} else if (!matches(*argv, "oseq")) {
 			oflags |= GRE_SEQ;
+		} else if (!matches(*argv, "nooseq")) {
+			oflags &= ~GRE_SEQ;
 		} else if (!matches(*argv, "csum")) {
 			iflags |= GRE_CSUM;
 			oflags |= GRE_CSUM;
+		} else if (!matches(*argv, "nocsum")) {
+			iflags &= ~GRE_CSUM;
+			oflags &= ~GRE_CSUM;
 		} else if (!matches(*argv, "icsum")) {
 			iflags |= GRE_CSUM;
+		} else if (!matches(*argv, "noicsum")) {
+			iflags &= ~GRE_CSUM;
 		} else if (!matches(*argv, "ocsum")) {
 			oflags |= GRE_CSUM;
+		} else if (!matches(*argv, "noocsum")) {
+			oflags &= ~GRE_CSUM;
 		} else if (!matches(*argv, "nopmtudisc")) {
 			pmtudisc = 0;
 		} else if (!matches(*argv, "pmtudisc")) {
diff --git a/ip/link_gre6.c b/ip/link_gre6.c
index a6fe0b73..181b2eae 100644
--- a/ip/link_gre6.c
+++ b/ip/link_gre6.c
@@ -38,9 +38,9 @@ static void gre_print_help(struct link_util *lu, int argc, char **argv, FILE *f)
 	);
 	fprintf(f,
 		"                     [ local ADDR ]\n"
-		"                     [ [i|o]seq ]\n"
-		"                     [ [i|o]key KEY ]\n"
-		"                     [ [i|o]csum ]\n"
+		"                     [ [no][i|o]seq ]\n"
+		"                     [ [i|o]key KEY | no[i|o]key ]\n"
+		"                     [ [no][i|o]csum ]\n"
 		"                     [ hoplimit TTL ]\n"
 		"                     [ encaplimit ELIM ]\n"
 		"                     [ tclass TCLASS ]\n"
@@ -220,28 +220,52 @@ get_failed:
 			iflags |= GRE_KEY;
 			oflags |= GRE_KEY;
 			ikey = okey = tnl_parse_key("key", *argv);
+		} else if (!matches(*argv, "nokey")) {
+			iflags &= ~GRE_KEY;
+			oflags &= ~GRE_KEY;
+			ikey = okey = 0;
 		} else if (!matches(*argv, "ikey")) {
 			NEXT_ARG();
 			iflags |= GRE_KEY;
 			ikey = tnl_parse_key("ikey", *argv);
+		} else if (!matches(*argv, "noikey")) {
+			iflags &= ~GRE_KEY;
+			ikey = 0;
 		} else if (!matches(*argv, "okey")) {
 			NEXT_ARG();
 			oflags |= GRE_KEY;
 			okey = tnl_parse_key("okey", *argv);
+		} else if (!matches(*argv, "nookey")) {
+			oflags &= ~GRE_KEY;
+			okey = 0;
 		} else if (!matches(*argv, "seq")) {
 			iflags |= GRE_SEQ;
 			oflags |= GRE_SEQ;
+		} else if (!matches(*argv, "noseq")) {
+			iflags &= ~GRE_SEQ;
+			oflags &= ~GRE_SEQ;
 		} else if (!matches(*argv, "iseq")) {
 			iflags |= GRE_SEQ;
+		} else if (!matches(*argv, "noiseq")) {
+			iflags &= ~GRE_SEQ;
 		} else if (!matches(*argv, "oseq")) {
 			oflags |= GRE_SEQ;
+		} else if (!matches(*argv, "nooseq")) {
+			oflags &= ~GRE_SEQ;
 		} else if (!matches(*argv, "csum")) {
 			iflags |= GRE_CSUM;
 			oflags |= GRE_CSUM;
+		} else if (!matches(*argv, "nocsum")) {
+			iflags &= ~GRE_CSUM;
+			oflags &= ~GRE_CSUM;
 		} else if (!matches(*argv, "icsum")) {
 			iflags |= GRE_CSUM;
+		} else if (!matches(*argv, "noicsum")) {
+			iflags &= ~GRE_CSUM;
 		} else if (!matches(*argv, "ocsum")) {
 			oflags |= GRE_CSUM;
+		} else if (!matches(*argv, "noocsum")) {
+			oflags &= ~GRE_CSUM;
 		} else if (!matches(*argv, "remote")) {
 			NEXT_ARG();
 			get_addr(&daddr, *argv, AF_INET6);
diff --git a/man/man8/ip-link.8.in b/man/man8/ip-link.8.in
index 77ab8a3b..83ef3cae 100644
--- a/man/man8/ip-link.8.in
+++ b/man/man8/ip-link.8.in
@@ -775,12 +775,14 @@ the following additional arguments are supported:
 .BR type " { " gre " | " gretap " }"
 .BI " remote " ADDR " local " ADDR
 [
-.RB [ i | o ] seq
+.RB [ no ] "" [ i | o ] seq
 ] [
 .RB [ i | o ] key
 .I KEY
+|
+.BR no [ i | o ] key
 ] [
-.RB [ i | o ] csum
+.RB [ no ] "" [ i | o ] csum
 ] [
 .BI ttl " TTL "
 ] [
@@ -816,7 +818,7 @@ the following additional arguments are supported:
 It must be an address on another interface on this host.
 
 .sp
-.RB [ i | o ] seq
+.RB  [ no ] "" [ i | o ] seq
 - serialize packets.
 The
 .B oseq
@@ -828,6 +830,8 @@ flag requires that all input packets are serialized.
 .sp
 .RB [ i | o ] key
 .I KEY
+|
+.BR no [ i | o ] key
 - use keyed GRE with key
 .IR KEY ". "KEY
 is either a number or an IPv4 address-like dotted quad.
@@ -839,7 +843,7 @@ The
 parameters specify different keys for input and output.
 
 .sp
-.RB  [ i | o ] csum
+.RB  [ no ] "" [ i | o ] csum
 - generate/require checksums for tunneled packets.
 The
 .B ocsum
@@ -920,12 +924,14 @@ the following additional arguments are supported:
 .BR type " { " ip6gre " | " ip6gretap " }"
 .BI remote " ADDR " local " ADDR"
 [
-.RB [ i | o ] seq
+.RB [ no ] "" [ i | o ] seq
 ] [
 .RB [ i | o ] key
 .I KEY
+|
+.BR no [ i | o ] key
 ] [
-.RB [ i | o ] csum
+.RB [ no ] "" [ i | o ] csum
 ] [
 .BI hoplimit " TTL "
 ] [
@@ -955,7 +961,7 @@ the following additional arguments are supported:
 It must be an address on another interface on this host.
 
 .sp
-.RB  [ i | o ] seq
+.RB  [ no ] "" [ i | o ] seq
 - serialize packets.
 The
 .B oseq
@@ -965,7 +971,10 @@ The
 flag requires that all input packets are serialized.
 
 .sp
-.RB  [ i | o ] key " \fIKEY"
+.RB [ i | o ] key
+.I KEY
+|
+.BR no [ i | o ] key
 - use keyed GRE with key
 .IR KEY ". "KEY
 is either a number or an IPv4 address-like dotted quad.
@@ -977,7 +986,7 @@ The
 parameters specify different keys for input and output.
 
 .sp
-.RB  [ i | o ] csum
+.RB  [ no ] "" [ i | o ] csum
 - generate/require checksums for tunneled packets.
 The
 .B ocsum