There are two differences between kissing at Ukrainian weddings and kissing at the weddings in Western world.

1.In North America or in Western Europe guests at weddings tap their wine glasses to get newlyweds to kiss.
At Ukrainian weddings guests sing a special song to make the bride and groom kiss:
"Oy girka horilka,
Ne budemo pyty,
Prosym molodogo
Ta y posolodyty!
Girko! Girko!"
It means literally,"Horilka is too bitter, we will not drink it; we ask the groom to add some sugar to. Bitter! Bitter!"Then the newlyweds have to kiss.

2.Bride and groom are the only ones asked to kiss at West European or North American weddings.
At a Ukrainian wedding not only the newlyweds are kissing, but each groomsman is suppose to kiss his bridesmaid. To make the bridesmaid and groomsman kiss, Ukrainians have a special song too:
"Ne budemo pyty
Tu girkuyu yushku
Nekhai potsilue
Starshyy druzhba druzhku.
Girko! Girko!"
The translation is almost the same as in the song for newlyweds, "We do not want this bitter drink, let the first groomsman kiss his bridesmaid! Bitter! Bitter!"
The guests are singing the same song to the second bridesmaid and second groomsman. I told already in one of my articles that bridesmaids and groomsmen get a special rank at a Ukrainian wedding: to be a first bridesmaid (persha druzhkaorstarsha druzhka) and a second bridesmaid (druga druzhkaormolodsha druzhka); to be a first groomsman (pershyy druzhbaorstarshyy druzhba) and a second groomsman (drugyy druzhbaormolodshyy druzhba).

In some cases, when groomsman is too confused or too shy to kiss his bridesmaid, people are singing to him, "What a best man, what a fool, he is scared of bridesmaid like she is wearing a gas mask!". I have been to many Ukrainian weddings, but I do not remember any groomsman which would resist kissing his bridesmaid after that song.