Problem with namespaces

Cannot use Nette\Application\UI\Presenter as Presenter 
because the name is already in use

File: .../app/Microsite/Application/ErrorPresenter.php:7

<?php
namespace Microsite\Application;

use Exception;
use Nette\Application\BadRequestException;
---> use Nette\Application\UI\Presenter;
use Tracy\Debugger;