The clubs have traded four players between each other this summer.
Unai Emery has laughed off the notion of a cosy relationship between Chelsea and Villa declaring: “We want to kill each other.”
Emi Martinez became the fourth player to move between the Premier League rivals this summer when he completed a £7.5million switch on Sunday.
The goalkeeper has joined Morgan Rogers at Stamford Bridge, with Nicolas Jackson and Alejandro Garnacho having moved in the opposite direction.
It brought the number of deals between the clubs to eight in the past four years. No two Premier League sides have exchanged more players in that time.
Villa co-owner Nassef Sawiris and Chelsea counterpart Behdad Eghbali are known to have a strong working relationship, which was key to negotiations when Rogers moved in a £117m British record transfer.
But Emery says any friendliness begins and ends in the boardroom.
Asked how important it was to have strong relationships with other clubs, he replied: “Good relations? The relationship is only through the deals for money and the players.
“They want to kill us - and we want to kill them! It is not a good relationship.
“We do deals because of course we have good players and we can sign players from them.
“But it is not a good relationship. It is a deal for money and players and they will want to kill us.
“They are signing Morgan and Emiliano Martinez to kill us.
“Of course, I am happy for the players. I am happy for Martinez and I am happy for Morgan Rogers. But I am not happy for Chelsea!”
This summer’s deals are likely to be scrutinised by Uefa, who have the power to limit the profit clubs can record on transfers deemed to be “swaps”.
Villa and Chelsea, who are both subject to sanction agreements with the governing body following previous breaches of financial rules, will argue all four deals were independent of each other.