The Gunners dropped two crucial points in the Premier League title race after Leandro Trossard had put them ahead in the 66th minute, with Ivan Toney nodding home a 74th-minute leveller.
But Arteta claimed Toney’s goal shouldn’t have stood, with Ethan Pinnock being offside initially from the set-piece, blocking Gabriel Magalhaes from getting to the first ball.
“I just looked it back and it is offside yeah,” Arteta told reporters. “It is (frustrating) but probably they will give an explanation later in the week.
“But today we havent got any, looking at the images, you have to apply certain principles in defending and you do that by sticking to the rules and suddenly you apply different rules you have to change your principles.
“Tell us before because then you dont hide the line that high because you have an advantage you get blocked.
“The action when you get blocked when you are offside, you cannot block when you are offside.”
Arteta also pointed to Christian Norgaard being in an apparent offside position before he flicked the ball across for the decisive header.
“Maybe I’m hoping it’s the camera, the visual, it looks like the actual action,” Arteta said. “I don’t know, it’s too late, the goal was allowed. We dropped two points.
“I’m saying the second one I do not know, because you have to see the line the way they see it with the camera, It’s irrelevant, it’s gone.”
Arteta added that the Gunners will seek an explanation from the Premier League around the decision.
“We always assess with them,” he said. “We give our views and our points but its late. Too late.”