The MP's comments come just a few days after the EU Court upheld bans on headscarves by two employers in Belgium and France.
Hagen wants to use the ruling for a basis to ban all municipal employees from wearing political, religious or philosophical symbols at work, reports newspaper VG.
But Hagen's call for a ban in Oslo is unlikely to gain much traction, according to municipality politicians.
Councillor Tone Tellevik Dahl of the Labour Party (Arbeiderpartiet) said that she found the bearing of religious symbols at work unproblematic.
“With the current majority [for the Labour Party in Oslo Municipality, ed.] it seems unlikely that he will get anywhere,” Dahl told VG.
Labour's gender equality and anti-discrimination ombud Hanne Bjurstrøm said that religious headwear is strongly protected and that many have misconstrued the EU judgement.
“In the public debate this has been presented as though it is now fair game to ban employees from wearing hijabs at work. This is a misunderstanding. The judgement states that a ban can be indirectly discriminative. At the same time, the Court has left a lot of discretion to national courts to decide where the boundaries should go,” Bjurstrøm told VG.