Can I resize a GADBannerView?

I'm using a custom GADBannerView in my application. Currently I'm getting the following frame.

<GADBannerView: 0x7fd146f9d8a0; frame = (0 0; 640 260); clipsToBounds = YES; layer = <CALayer: 0x7fd1455a2880>>

Can I resize the frame to 320x130? If I resize it I get a "No ads to display" error. If I keep it the original size I receive ads.

Is there is any way to change the size of GADBannerView?