{!! Form::open(['url' =>  $url, 'id' => 'payment', 'class' => 'form-horizontal']) !!}
    @foreach($fields as $key => $value)
        {!! Form::hidden($key, $value) !!}
    @endforeach
{!! Form::close() !!}

<script type="text/javascript">
    document.getElementById('payment').submit();
</script>