How to say "You are lying!"


How do I say "You are lying!" in a joking way?

Can I say:

> 嘘{うそ}だよ

or is there a friendlier way to say it?




Another is:

[うそつけ
(嘘{うそ}吐{つ}け)](http://www.weblio.jp/content/%E3%81%86%E3%81%9D%E3%81%A4%E3%81%91)！
- Liar! Comes from 嘘｛うそ｝をつく, to lie

From comments:

[うそつき (嘘{うそ}吐{つ}き)](http://dictionary.goo.ne.jp/jn/19011/meaning/m0u/) - Liar;
Someone who lies

