Telephone number
strict international section :- starting with '+' or '00'
flexible local section for wider international and allows spaces for visual formatting
Close enough for many requirements. Tweak to match your country/circumstances better.
Matches:
+1 123456
001 123456
001123456
+1123456
+32 123456
+32 123 456
0032 123456
+32 123 456
+32123456
00354 123456
+354 123456
+354123456