Deleted member 94680
No. Just no.
The original meaning of the United Nations was the nations that fought united against the Axis. Pointedly, the countries that are a suitable OTL comparison to this ATL Italy, i.e. Spain and Portugal, joined in 1955.
And the five countries that, to date, have a permanent seat in the Security Council and therefore a veto power are the top five powers that defeated the Axis. Even minor allies of those powers, say Belgium or Greece, have no such power. Even the parts of the British Commowealth that were there, provided the British with invaluable help, and are now independent, say Canada or Australia, have no permanent seat.
Coincidentally, the 5 Permanent Members of the UNSC also just happen to be Nuclear Weapon States as well.