The front rounded vowels defined by the IPA include: Front rounded vowels are cross-linguistically relatively uncommon, but occur in a number of well-known languages, including French, German, Turkish, and Mandarin.
This is harder to do while producing low or open vowels since the lips are being stressed vertically.
[1] Most languages with front rounded vowels are found in the more northern parts of Eurasia.
For example, the familiar second-person pronoun tu, pronounced [ty], is spelled the same as its Latin source tu which had a back vowel, and the plural or polite second-person pronoun vous is pronounced with [u], but it derives from Latin vos which had a mid vowel.
In cases like these the creation of front rounded vowels is independent of adjacent sounds in the word.
[1] Considering the different historical scenarios which can give rise to front rounded vowels, it is notable that they are relatively concentrated in a particular geographical region.