diff --git a/avm/res/compute/virtual-machine/README.md b/avm/res/compute/virtual-machine/README.md
index 3302521f67..f6fc002f01 100644
--- a/avm/res/compute/virtual-machine/README.md
+++ b/avm/res/compute/virtual-machine/README.md
@@ -3213,7 +3213,6 @@ Specifies the OS disk. For security reasons, it is recommended to specify DiskEn
 
 | Parameter | Type | Description |
 | :-- | :-- | :-- |
-| [`diskSizeGB`](#parameter-osdiskdisksizegb) | int | Specifies the size of an empty data disk in gigabytes. |
 | [`managedDisk`](#parameter-osdiskmanageddisk) | object | The managed disk parameters. |
 
 **Optional parameters**
@@ -3223,15 +3222,9 @@ Specifies the OS disk. For security reasons, it is recommended to specify DiskEn
 | [`caching`](#parameter-osdiskcaching) | string | Specifies the caching requirements. |
 | [`createOption`](#parameter-osdiskcreateoption) | string | Specifies how the virtual machine should be created. |
 | [`deleteOption`](#parameter-osdiskdeleteoption) | string | Specifies whether data disk should be deleted or detached upon VM deletion. |
+| [`diskSizeGB`](#parameter-osdiskdisksizegb) | int | Specifies the size of an empty data disk in gigabytes. |
 | [`name`](#parameter-osdiskname) | string | The disk name. |
 
-### Parameter: `osDisk.diskSizeGB`
-
-Specifies the size of an empty data disk in gigabytes.
-
-- Required: Yes
-- Type: int
-
 ### Parameter: `osDisk.managedDisk`
 
 The managed disk parameters.
@@ -3239,23 +3232,25 @@ The managed disk parameters.
 - Required: Yes
 - Type: object
 
-**Required parameters**
+**Optional parameters**
 
 | Parameter | Type | Description |
 | :-- | :-- | :-- |
+| [`diskEncryptionSetResourceId`](#parameter-osdiskmanageddiskdiskencryptionsetresourceid) | string | Specifies the customer managed disk encryption set resource id for the managed disk. |
 | [`storageAccountType`](#parameter-osdiskmanageddiskstorageaccounttype) | string | Specifies the storage account type for the managed disk. |
 
-**Optional parameters**
+### Parameter: `osDisk.managedDisk.diskEncryptionSetResourceId`
 
-| Parameter | Type | Description |
-| :-- | :-- | :-- |
-| [`diskEncryptionSetResourceId`](#parameter-osdiskmanageddiskdiskencryptionsetresourceid) | string | Specifies the customer managed disk encryption set resource id for the managed disk. |
+Specifies the customer managed disk encryption set resource id for the managed disk.
+
+- Required: No
+- Type: string
 
 ### Parameter: `osDisk.managedDisk.storageAccountType`
 
 Specifies the storage account type for the managed disk.
 
-- Required: Yes
+- Required: No
 - Type: string
 - Allowed:
   ```Bicep
@@ -3270,13 +3265,6 @@ Specifies the storage account type for the managed disk.
   ]
   ```
 
-### Parameter: `osDisk.managedDisk.diskEncryptionSetResourceId`
-
-Specifies the customer managed disk encryption set resource id for the managed disk.
-
-- Required: No
-- Type: string
-
 ### Parameter: `osDisk.caching`
 
 Specifies the caching requirements.
@@ -3321,6 +3309,13 @@ Specifies whether data disk should be deleted or detached upon VM deletion.
   ]
   ```
 
+### Parameter: `osDisk.diskSizeGB`
+
+Specifies the size of an empty data disk in gigabytes.
+
+- Required: No
+- Type: int
+
 ### Parameter: `osDisk.name`
 
 The disk name.
diff --git a/avm/res/compute/virtual-machine/main.bicep b/avm/res/compute/virtual-machine/main.bicep
index ce60427363..3125725bdb 100644
--- a/avm/res/compute/virtual-machine/main.bicep
+++ b/avm/res/compute/virtual-machine/main.bicep
@@ -1145,8 +1145,8 @@ type osDiskType = {
   @description('Optional. The disk name.')
   name: string?
 
-  @description('Required. Specifies the size of an empty data disk in gigabytes.')
-  diskSizeGB: int
+  @description('Optional. Specifies the size of an empty data disk in gigabytes.')
+  diskSizeGB: int?
 
   @description('Optional. Specifies how the virtual machine should be created.')
   createOption: 'Attach' | 'Empty' | 'FromImage'?
@@ -1159,7 +1159,7 @@ type osDiskType = {
 
   @description('Required. The managed disk parameters.')
   managedDisk: {
-    @description('Required. Specifies the storage account type for the managed disk.')
+    @description('Optional. Specifies the storage account type for the managed disk.')
     storageAccountType:
       | 'PremiumV2_LRS'
       | 'Premium_LRS'
@@ -1167,7 +1167,7 @@ type osDiskType = {
       | 'StandardSSD_LRS'
       | 'StandardSSD_ZRS'
       | 'Standard_LRS'
-      | 'UltraSSD_LRS'
+      | 'UltraSSD_LRS'?
 
     @description('Optional. Specifies the customer managed disk encryption set resource id for the managed disk.')
     diskEncryptionSetResourceId: string?
diff --git a/avm/res/compute/virtual-machine/main.json b/avm/res/compute/virtual-machine/main.json
index 202bb809dc..0f6e43482d 100644
--- a/avm/res/compute/virtual-machine/main.json
+++ b/avm/res/compute/virtual-machine/main.json
@@ -6,7 +6,7 @@
     "_generator": {
       "name": "bicep",
       "version": "0.26.54.24096",
-      "templateHash": "8007594709688742996"
+      "templateHash": "5878958605426596334"
     },
     "name": "Virtual Machines",
     "description": "This module deploys a Virtual Machine with one or multiple NICs and optionally one or multiple public IPs.",
@@ -139,8 +139,9 @@
         },
         "diskSizeGB": {
           "type": "int",
+          "nullable": true,
           "metadata": {
-            "description": "Required. Specifies the size of an empty data disk in gigabytes."
+            "description": "Optional. Specifies the size of an empty data disk in gigabytes."
           }
         },
         "createOption": {
@@ -192,8 +193,9 @@
                 "Standard_LRS",
                 "UltraSSD_LRS"
               ],
+              "nullable": true,
               "metadata": {
-                "description": "Required. Specifies the storage account type for the managed disk."
+                "description": "Optional. Specifies the storage account type for the managed disk."
               }
             },
             "diskEncryptionSetResourceId": {