The signature seems to be something like "Fonterreir" . Sounds French. However, I googled it with no results.
The decoration doesn't look like any french art nouveau, that I know of. I believe the white decorations are painted? Painted, transparent glass is very atypical of the art nouveau period.
Smoke colored glass was used in early 20th century, for example by Daum and Schneider, but was usually sand blasted with art deco patterns. It was also more brownish than this vase, which has a more greenish teint.
I'd go for the 60s 70s art glass option.
\bablo