Arsenal won the Premier League title this season — their first in 22 years — but fell to PSG on penalties after extra time at Puskás Aréna, with Gabriel Magalhães blazing his spot-kick over the bar to hand the French champions a second successive European trophy.
Arteta was direct in his post-match assessment.
"We will need to start making some very important decisions if we want to reach a new level.
"And we will need to show that ambition because we are more than capable of doing it, but it will require being very, very ambitious, very fast and very smart."
The Athletic's David Ornstein reports that the left side of Arsenal's attack is Arteta's primary recruitment focus, with improved options needed on the wing and at centre-forward. The names currently leading the shortlist are Morgan Rogers (Aston Villa), Julián Álvarez (Atletico Madrid) and Eli Junior Kroupi (Bournemouth) — none of whom will come cheaply.
To fund that ambition, Arsenal are prepared to move on several players.
BBC Sport reports that Gabriel Jesus, Gabriel Martinelli and Leandro Trossard are all available for offers, with the club open to bids for all three. Ethan Nwaneri, Christian Nørgaard and Ben White are also considered potentially saleable. Two players currently out on loan — Fabio Vieira and Reiss Nelson — are expected to leave on a permanent basis.
A potential acquisition that is already in discussion is the signing of West Ham United midfielder Mateus Fernandes.
Arsenal's financial position is described as strong after a season that combined Premier League glory and a run to the European final, and the club intends to use that position aggressively.
PSG's quality in individual moments — the precise factor Arteta pointed to in his press conference — will set the standard that this summer's business is designed to meet.