diff --git a/pkg/core/interop/context.go b/pkg/core/interop/context.go
index b1e400624..5d96a9493 100644
--- a/pkg/core/interop/context.go
+++ b/pkg/core/interop/context.go
@@ -82,6 +82,7 @@ type ContractMD struct {
 	Manifest    manifest.Manifest
 	ServiceName string
 	ServiceID   uint32
+	ContractID  int32
 	Script      []byte
 	Hash        util.Uint160
 	Methods     map[string]MethodAndPrice
diff --git a/pkg/core/native/native_gas.go b/pkg/core/native/native_gas.go
index 109deceb3..ea98b80f3 100644
--- a/pkg/core/native/native_gas.go
+++ b/pkg/core/native/native_gas.go
@@ -20,6 +20,7 @@ type GAS struct {
 }
 
 const gasSyscallName = "Neo.Native.Tokens.GAS"
+const gasContractID = -2
 
 // GASFactor is a divisor for finding GAS integral value.
 const GASFactor = NEOTotalSupply
@@ -35,6 +36,7 @@ func NewGAS() *GAS {
 	nep5.factor = GASFactor
 	nep5.onPersist = chainOnPersist(g.onPersist, g.OnPersist)
 	nep5.incBalance = g.increaseBalance
+	nep5.ContractID = gasContractID
 
 	g.nep5TokenNative = *nep5
 
diff --git a/pkg/core/native/native_neo.go b/pkg/core/native/native_neo.go
index 84b85cf74..2dfd4b2f6 100644
--- a/pkg/core/native/native_neo.go
+++ b/pkg/core/native/native_neo.go
@@ -34,6 +34,7 @@ type keyWithVotes struct {
 
 const (
 	neoSyscallName = "Neo.Native.Tokens.NEO"
+	neoContractID  = -2
 	// NEOTotalSupply is the total amount of NEO in the system.
 	NEOTotalSupply = 100000000
 	// prefixValidator is a prefix used to store validator's data.
@@ -69,6 +70,7 @@ func NewNEO() *NEO {
 	nep5.factor = 1
 	nep5.onPersist = chainOnPersist(n.onPersist, n.OnPersist)
 	nep5.incBalance = n.increaseBalance
+	nep5.ContractID = neoContractID
 
 	n.nep5TokenNative = *nep5