diff --git a/lighthouse/tests/validator_client.rs b/lighthouse/tests/validator_client.rs
index 062b7e7786a..4420a980616 100644
--- a/lighthouse/tests/validator_client.rs
+++ b/lighthouse/tests/validator_client.rs
@@ -427,6 +427,21 @@ fn no_doppelganger_protection_flag() {
         .run()
         .with_config(|config| assert!(!config.enable_doppelganger_protection));
 }
+#[test]
+fn produce_block_v3_flag() {
+    CommandLineTest::new()
+        .flag("produce-block-v3", None)
+        .run()
+        .with_config(|config| assert!(config.produce_block_v3));
+}
+
+#[test]
+fn no_produce_block_v3_flag() {
+    CommandLineTest::new()
+        .run()
+        .with_config(|config| assert!(!config.produce_block_v3));
+}
+
 #[test]
 fn block_delay_ms() {
     CommandLineTest::new()
diff --git a/validator_client/src/block_service.rs b/validator_client/src/block_service.rs
index d4afb911330..a05fe3a480c 100644
--- a/validator_client/src/block_service.rs
+++ b/validator_client/src/block_service.rs
@@ -334,18 +334,8 @@ impl<T: SlotClock + 'static, E: EthSpec> BlockService<T, E> {
             )
         }
 
-        let deneb_fork_activated = self
-            .context
-            .eth2_config
-            .spec
-            .altair_fork_epoch
-            .and_then(|fork_epoch| {
-                let current_epoch = self.slot_clock.now()?.epoch(E::slots_per_epoch());
-                Some(current_epoch >= fork_epoch)
-            })
-            .unwrap_or(false);
-
-        if deneb_fork_activated {
+        // TODO: activate automatically at Deneb
+        if !self.validator_store.produce_block_v3() {
             for validator_pubkey in proposers {
                 let service = self.clone();
                 let log = log.clone();
@@ -457,6 +447,7 @@ impl<T: SlotClock + 'static, E: EthSpec> BlockService<T, E> {
         Ok(())
     }
 
+    #[allow(clippy::too_many_arguments)]
     async fn handle_block_response<Payload: AbstractExecPayload<E>>(
         &self,
         log: &Logger,
diff --git a/validator_client/src/cli.rs b/validator_client/src/cli.rs
index 0af92a9e39a..4aa0eb6f987 100644
--- a/validator_client/src/cli.rs
+++ b/validator_client/src/cli.rs
@@ -153,6 +153,14 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                 .value_name("FEE-RECIPIENT")
                 .takes_value(true)
         )
+        .arg(
+            Arg::with_name("produce-block-v3")
+                .long("produce-block-v3")
+                .help("Enable block production via the block v3 endpoint for this validator client. \
+                       This should only be enabled when paired with a beacon node \
+                       that has this endpoint implemented.")
+                .takes_value(false)
+        )
         /* REST API related arguments */
         .arg(
             Arg::with_name("http")
diff --git a/validator_client/src/config.rs b/validator_client/src/config.rs
index 7c662db9371..a90bc21fcf0 100644
--- a/validator_client/src/config.rs
+++ b/validator_client/src/config.rs
@@ -79,6 +79,8 @@ pub struct Config {
     pub enable_latency_measurement_service: bool,
     /// Defines the number of validators per `validator/register_validator` request sent to the BN.
     pub validator_registration_batch_size: usize,
+    /// Enables block production via the block v3 endpoint. This configuration option can be removed post deneb.
+    pub produce_block_v3: bool,
 }
 
 impl Default for Config {
@@ -120,6 +122,7 @@ impl Default for Config {
             disable_run_on_all: false,
             enable_latency_measurement_service: true,
             validator_registration_batch_size: 500,
+            produce_block_v3: false,
         }
     }
 }
@@ -361,6 +364,10 @@ impl Config {
             config.builder_proposals = true;
         }
 
+        if cli_args.is_present("produce-block-v3") {
+            config.produce_block_v3 = true;
+        }
+
         config.gas_limit = cli_args
             .value_of("gas-limit")
             .map(|gas_limit| {
diff --git a/validator_client/src/validator_store.rs b/validator_client/src/validator_store.rs
index 365f7f73474..703b6901b3c 100644
--- a/validator_client/src/validator_store.rs
+++ b/validator_client/src/validator_store.rs
@@ -97,6 +97,7 @@ pub struct ValidatorStore<T, E: EthSpec> {
     fee_recipient_process: Option<Address>,
     gas_limit: Option<u64>,
     builder_proposals: bool,
+    produce_block_v3: bool,
     task_executor: TaskExecutor,
     _phantom: PhantomData<E>,
 }
@@ -128,6 +129,7 @@ impl<T: SlotClock + 'static, E: EthSpec> ValidatorStore<T, E> {
             fee_recipient_process: config.fee_recipient,
             gas_limit: config.gas_limit,
             builder_proposals: config.builder_proposals,
+            produce_block_v3: config.produce_block_v3,
             task_executor,
             _phantom: PhantomData,
         }
@@ -336,6 +338,10 @@ impl<T: SlotClock + 'static, E: EthSpec> ValidatorStore<T, E> {
         self.spec.fork_at_epoch(epoch)
     }
 
+    pub fn produce_block_v3(&self) -> bool {
+        self.produce_block_v3
+    }
+
     /// Returns a `SigningMethod` for `validator_pubkey` *only if* that validator is considered safe
     /// by doppelganger protection.
     fn doppelganger_checked_signing_method(