A method of selecting a promotional content for media content items. The method comprises providing a database hosting a plurality of uniform resource locators (URLs) each of a web document through which at least one of a plurality of media content items being available for presentation, receiving an ad request for embedding an in stream advertisement in a media content item, analyzing the ad request to extract a video content URL of a certain web document through which the media content item is made available for presentation, matching between the video content URL and at least one of the plurality of URLs to acquire at least one identifier of the media content item, selecting an in stream advertisement based on the at least one identifier, and responding to the ad request with an indication of the in stream advertisement.