It’s actually quite natural to call your love, male or female, a sun – as a pet name. Let’s finish off with the must-know, most common love phrase – I love you.
At Ukraine also exists such thing as a mix of both languages.
or you’re already in a Western country, then go ahead and use it.
By the way, this phrase is in feminine form, so it’s meant to be used on a female listener.
Though for people from Russia someone who speaks Ukrainian sounds rather odd and sometimes funny.
Both have the same origins but the history shaped them a lot different and, please, don’t think that it is the same language.