diff --git a/ibc/modules/src/core/ics02_client/handler/upgrade_client.rs b/ibc/modules/src/core/ics02_client/handler/upgrade_client.rs
index 09a945b02..4d39d5b49 100644
--- a/ibc/modules/src/core/ics02_client/handler/upgrade_client.rs
+++ b/ibc/modules/src/core/ics02_client/handler/upgrade_client.rs
@@ -17,6 +17,7 @@
 use crate::{
 	core::{
 		ics02_client::{
+			client_consensus::ConsensusState,
 			client_def::{ClientDef, ConsensusUpdateResult},
 			client_state::ClientState,
 			context::ClientTypes,
@@ -60,6 +61,29 @@ where
 		return Err(Error::client_frozen(client_id))
 	}
 
+	// need to ensure that the client state is not expired as per
+	// https://github.com/cosmos/ibc-rs/blob/main/docs/architecture/adr-006-upgrade-client-implementation.md#decisions
+	let latest_consensus_state =
+		ctx.consensus_state(&client_id, client_state.latest_height()).map_err(|_| {
+			Error::consensus_state_not_found(client_id.clone(), client_state.latest_height())
+		})?;
+
+	tracing::debug!("latest consensus state: {:?}", latest_consensus_state);
+
+	let now = ctx.host_timestamp();
+	let last_update_timestamp =
+		ctx.client_update_time(&client_id, client_state.latest_height()).map_err(|_| {
+			Error::implementation_specific("Could not find update time for client".to_string())
+		})?;
+
+	let duration = now.duration_since(&last_update_timestamp).ok_or_else(|| {
+		Error::invalid_consensus_state_timestamp(latest_consensus_state.timestamp(), now)
+	})?;
+
+	if client_state.expired(duration) {
+		return Err(Error::header_not_within_trust_period(last_update_timestamp, now))
+	}
+
 	let upgrade_client_state = msg.client_state.clone();
 
 	if client_state.latest_height() >= upgrade_client_state.latest_height() {