Expression: Not on your Nellie!

“Not on your Nellie!” is used in Britain like “No way!” in the US. It means “absolutely not.”
Below is an example used twice in Only Fools And Horses, starring the very popular David Jason, as 0:35 and 1:20.

Other expressions used in this video:
0:27 “I thought you were bluffing!” – “Bluff” means to pretend you are going to do something, when you actually had no intention, so in poker it means showing confidence in his ‘hand’ (the cards in his hand) that he will win, when actually his hand is not very good.
0:52 “You couldn’t give us a lift home, could you?” – Southern British , especially London, often use “us” instead of “me”. I don’t know why!
2:06 “Four aces! I ain’t never seen it before!” – Again, it is the South England dialect. “Ain’t” is the useful slang verb meaning “am not”, “have not”, “is not”, “has not”, “are not”. It makes grammar much easier! He also used a double negative with “never”, which is wrong but very common.
2:20 “I thought Delboy might have something up his sleeve.” The idiom to have something up your sleeve means you have a plan in case of a problem, but in this case Delboy reacted negatively because maybe he actually had a card up his sleeve of his shirt – meaning cheating.
2:30 “What is your game?” is an idiom meaning “What are you doing?”
The final sentence was “I knew you was (were) cheating Boycey, because that wasn’t the hand that I dealt you!” meaning that Delboy knew Boycey was cheating because Delboy knew what cards he had given Boycey. How could Delboy have known this? Well, Delboy was also cheating!