How to create a new resource in Azure ARM templates?

Ok, I did everything that described here - https://azure.microsoft.com/en-us/documentation/articles/app-service-vnet-integration-powershell/ with ARM templates. The only task I don't know how to do with template is the following command:

$vnet = New-AzureRmResource -Name "$($Configuration.WebAppName)/$($Configuration.VnetName)/primary" -ResourceGroupName $Configuration.WebAppResourceGroup -ResourceType "Microsoft.Web/sites/virtualNetworkConnections/gateways" -ApiVersion 2015-07-01 -PropertyObject @{"VnetName" = $Configuration.VnetName ; "VpnPackageUri" = $($output.Outputs.packageUri).Value } -Location $Configuration.WebAppLocation

Or, put it in other way I can't 'Enabling VNET Integration with a pre-existing VNET' (from here - https://azure.microsoft.com/en-us/documentation/articles/web-sites-integrate-with-vnet). What's the alternative in ARM templates?

Thanks.