diff --git a/backend/drive/drive.go b/backend/drive/drive.go
index e6cac2b1c..a036c9a03 100644
--- a/backend/drive/drive.go
+++ b/backend/drive/drive.go
@@ -202,7 +202,7 @@ func init() {
 					m.Set("root_folder_id", "appDataFolder")
 				}
 
-				if opt.ServiceAccountFile == "" && opt.ServiceAccountCredentials == "" {
+				if opt.ServiceAccountFile == "" && opt.ServiceAccountCredentials == "" && !opt.EnvAuth {
 					return oauthutil.ConfigOut("teamdrive", &oauthutil.Options{
 						OAuth2Config: driveConfig,
 					})
@@ -598,6 +598,18 @@ resource key is no needed.
 			// Encode invalid UTF-8 bytes as json doesn't handle them properly.
 			// Don't encode / as it's a valid name character in drive.
 			Default: encoder.EncodeInvalidUtf8,
+		}, {
+			Name:     "env_auth",
+			Help:     "Get IAM credentials from runtime (environment variables or instance meta data if no env vars).\n\nOnly applies if service_account_file and service_account_credentials is blank.",
+			Default:  false,
+			Advanced: true,
+			Examples: []fs.OptionExample{{
+				Value: "false",
+				Help:  "Enter AWS credentials in the next step.",
+			}, {
+				Value: "true",
+				Help:  "Get GCP IAM credentials from the environment (env vars or IAM).",
+			}},
 		}}...),
 	})
 
@@ -654,6 +666,7 @@ type Options struct {
 	SkipDanglingShortcuts     bool                 `config:"skip_dangling_shortcuts"`
 	ResourceKey               string               `config:"resource_key"`
 	Enc                       encoder.MultiEncoder `config:"encoding"`
+	EnvAuth                   bool                 `config:"env_auth"`
 }
 
 // Fs represents a remote drive server
@@ -1122,6 +1135,12 @@ func createOAuthClient(ctx context.Context, opt *Options, name string, m configm
 		if err != nil {
 			return nil, fmt.Errorf("failed to create oauth client from service account: %w", err)
 		}
+	} else if opt.EnvAuth {
+		scopes := driveScopes(opt.Scope)
+		oAuthClient, err = google.DefaultClient(ctx, scopes...)
+		if err != nil {
+			return nil, fmt.Errorf("failed to create client from environment: %w", err)
+		}
 	} else {
 		oAuthClient, _, err = oauthutil.NewClientWithBaseClient(ctx, name, m, driveConfig, getClient(ctx, opt))
 		if err != nil {