diff --git a/walletkit_client.go b/walletkit_client.go
index dfa57c5..3dfbef9 100644
--- a/walletkit_client.go
+++ b/walletkit_client.go
@@ -111,6 +111,10 @@ type WalletKitClient interface {
 	EstimateFeeRate(ctx context.Context,
 		confTarget int32) (chainfee.SatPerKWeight, error)
 
+	// MinRelayFee returns the current minimum relay fee based on our chain
+	// backend in sat/kw.
+	MinRelayFee(ctx context.Context) (chainfee.SatPerKWeight, error)
+
 	// ListSweeps returns a list of sweep transaction ids known to our node.
 	// Note that this function only looks up transaction ids, and does not
 	// query our wallet for the full set of transactions. If startHeight is