Help needed identifying cartoon characters

I just bought a miserable old VHS cassette with five short animated cartoons. All the five films in the bunch were without opening titles, and I could recognize only one of the cartoons (a Filmation Popeye), some others were probably Terrytoons. I'll have to check into them later, but here's a photo I took of the first one. Does anyone recognize the characters in the picture? There's also a third cat, who's a kid brother or a nephew of the two in the picture. The cats spoke English under the lousy Finnish dubbing. I'm thinking this might be something Gene Deitch cooked up with Yugoslavian animators in the mid-to-late sixties.