According to the Gestalt psychology’s Law of proximity, things that are near to each other either physycally (in this case visually) or chronologically, are likely to be perceived as related.
So, if your header accomodates different kinds of link (e.g: some for the website navigations and some for the user’s account management) it’s a good and simple UX practice organizing them unequivocally in separated layout areas.
In this case, on the left website’s navigation and on the opposite site the e-commerce cart tools.

PS This post was just a lame excuse to show covertly some cute puppies.