diff --git a/yarn-project/aztec/src/bin/index.ts b/yarn-project/aztec/src/bin/index.ts
index b032f9d64714..ee13a912e714 100644
--- a/yarn-project/aztec/src/bin/index.ts
+++ b/yarn-project/aztec/src/bin/index.ts
@@ -12,11 +12,10 @@ import { createConsoleLogger, createLogger } from '@aztec/foundation/log';
 
 import { Command } from 'commander';
 
-import { NETWORK_FLAG, aztecStartOptions } from '../cli/aztec_start_options.js';
-import { enrichEnvironmentWithChainConfig } from '../cli/chain_l2_config.js';
+import { NETWORK_FLAG } from '../cli/aztec_start_options.js';
+import { type NetworkNames, enrichEnvironmentWithChainConfig } from '../cli/chain_l2_config.js';
 import { injectAztecCommands } from '../cli/index.js';
 import { getCliVersion } from '../cli/release_version.js';
-import { addOptions } from '../cli/util.js';
 
 const userLog = createConsoleLogger();
 const debugLogger = createLogger('cli');
@@ -29,15 +28,20 @@ async function main() {
   process.once('SIGINT', shutdown);
   process.once('SIGTERM', shutdown);
 
-  // We create a temp command object to detect the presence of the network option
-  // If it has been given then we enrich the environment with the chain config
-  const tempCmd = new Command('aztec').allowUnknownOption();
-  addOptions(tempCmd, aztecStartOptions['NETWORK']);
-  tempCmd.parse(process.argv);
-  const networkValue = tempCmd.getOptionValue(NETWORK_FLAG);
+  // Intercept the setting of a network and enrich the environment with defaults for that network
+  let networkValue: string | undefined;
+
+  const args = process.argv.slice(2);
+  const networkIndex = args.findIndex(arg => arg.startsWith(`--${NETWORK_FLAG}=`) || arg === `--${NETWORK_FLAG}`);
+
+  if (networkIndex !== -1) {
+    networkValue = args[networkIndex].split('=')[1] || args[networkIndex + 1];
+  }
+
+  networkValue = networkValue || process.env.NETWORK;
 
   if (networkValue !== undefined) {
-    await enrichEnvironmentWithChainConfig(networkValue);
+    await enrichEnvironmentWithChainConfig(networkValue as NetworkNames);
   }
 
   const cliVersion = getCliVersion();
diff --git a/yarn-project/aztec/src/cli/chain_l2_config.ts b/yarn-project/aztec/src/cli/chain_l2_config.ts
index f0cf184965f7..ad128399e8dd 100644
--- a/yarn-project/aztec/src/cli/chain_l2_config.ts
+++ b/yarn-project/aztec/src/cli/chain_l2_config.ts
@@ -1,3 +1,4 @@
+import { EthAddress } from '@aztec/aztec.js';
 import type { EnvVar } from '@aztec/foundation/config';
 
 import path from 'path';
@@ -92,6 +93,15 @@ function enrichVar(envVar: EnvVar, value: string) {
   process.env[envVar] = value;
 }
 
+function enrichEthAddressVar(envVar: EnvVar, value: string) {
+  // EthAddress doesn't like being given empty strings
+  if (value === '') {
+    enrichVar(envVar, EthAddress.ZERO.toString());
+    return;
+  }
+  enrichVar(envVar, value);
+}
+
 export async function enrichEnvironmentWithChainConfig(networkName: NetworkNames) {
   const config = await getL2ChainConfig(networkName);
   if (!config) {
@@ -106,12 +116,13 @@ export async function enrichEnvironmentWithChainConfig(networkName: NetworkNames
   enrichVar('SPONSORED_FPC', config.sponsoredFPC.toString());
   enrichVar('P2P_ENABLED', config.p2pEnabled.toString());
   enrichVar('L1_CHAIN_ID', config.l1ChainId.toString());
-  enrichVar('REGISTRY_CONTRACT_ADDRESS', config.registryAddress);
-  enrichVar('SLASH_FACTORY_CONTRACT_ADDRESS', config.slashFactoryAddress);
-  enrichVar('FEE_ASSET_HANDLER_CONTRACT_ADDRESS', config.feeAssetHandlerAddress);
   enrichVar('SEQ_MIN_TX_PER_BLOCK', config.seqMinTxsPerBlock.toString());
   enrichVar('SEQ_MAX_TX_PER_BLOCK', config.seqMaxTxsPerBlock.toString());
   enrichVar('DATA_DIRECTORY', path.join(process.env.HOME || '~', '.aztec', networkName, 'data'));
   enrichVar('PROVER_REAL_PROOFS', config.realProofs.toString());
   enrichVar('PXE_PROVER_ENABLED', config.realProofs.toString());
+
+  enrichEthAddressVar('REGISTRY_CONTRACT_ADDRESS', config.registryAddress);
+  enrichEthAddressVar('SLASH_FACTORY_CONTRACT_ADDRESS', config.slashFactoryAddress);
+  enrichEthAddressVar('FEE_ASSET_HANDLER_CONTRACT_ADDRESS', config.feeAssetHandlerAddress);
 }