Arsenal clearly need to sign new players in the transfer market despite stunning Liverpool, according to head coach Mikel Arteta.

Arteta's Arsenal received a boost in their rebuilding job, upstaging Premier League champions Liverpool 2-1 on Wednesday.

Arsenal trailed to Sadio Mane's opener and only claimed the lead after uncharacteristic Liverpool errors let in Alexandre Lacazette and Reiss Nelson midweek.

Despite the surprise victory, Arsenal – ninth in the table with two matches remaining – are 40 points behind Liverpool and Arteta insisted the Gunners must strengthen.

"I think it's pretty clear that we need to strengthen the squad," Arteta told reporters post-match.

Not since 2004 have Arsenal won the Premier League – failing to finish in the top four since their runners-up performance in 2015-16.

The gap has continued to widen in the Premier League, with Arsenal – who sacked Unai Emery in November – six points adrift of the top four.

Asked how long it will take to close the gap, Arteta said in a news conference: "Well I have seen it and I have experienced it. To do it in one year, and I have seen other clubs never do it. Or some clubs do it in four or five years.

"Depends on the context, depends on the resources, depends on how much you have to change.

"We are in a process, we don't know at the moment. There is a lot of uncertainty in many areas, what we can control now is who we want to be as a team, the culture we are building in order to do that, the spirit to be successful and then improve our players.

"My main focus is to make our players better, make them feel more comfortable and create an identity for the club because it will be easier to say we need this, this and this."

Arsenal are back in action against Manchester City in Saturday's FA Cup semi-final before visiting lowly Aston Villa in the Premier League on Tuesday.