何なにを言いうてんねん

also: なにをゆうてんねん

Meanings

Kansai-ben phrase expressing disbelief, frustration, or strong disagreement with what someone just said. Roughly equivalent to standard Japanese 何を言ってるんだよ.

「明日あしたからダイエットするわ」って、何なにを言いうてんねん。昨日きのうも同おなじこと言いうてたやろ。
"I'm going on a diet starting tomorrow" — what the hell are you saying? You said the same thing yesterday, didn't you?
何なにをゆうてんねん、そんなわけないやろ。
What the hell are you talking about? There's no way that's true.