laravel 5.5: how can I call route in controller?

in web.php I have this routes:

$this->namespace('Users')->prefix('users')->group(function (){
    $this->get('/create' , 'UserController@create');
});

this Route opens a form.

And

theis Route use for return arrays of countires. I use that array to fill a select box via ajax in the form.

Route::namespace('API')->prefix('api')->group(function (){
  $this->get('/get-country-list','LocationsController@index');
});

Controller:

app\Http\Controllers\API\LocationsController

class LocationsController extends Controller
{
  public function index()
  {
      return DB::table('countries')->pluck("name","id")->all();
  }
  .
  .
  .

app\Http\Controllers\Users\UserController

class UserController extends Controller
{
    public function create()
    {
        return view('panel.users.home.create.show');
    }
    .
    .
    .

How can I call LocationsController@index in create() function? what is the best method?

via Chebli Mohamed