This paper examines the understudied phenomenon of consonant gemination in the pronunciation of English among Levantine Arabic learners of English (LA learners). The very few studies that touched on gemination among LA learners attributed gemination to spelling in the target language (English). This study challenges this analysis and demonstrates that gemination is primarily a phonological phenomenon that is triggered by first language under-represented structural rules as well as Universal Grammar (UG) markedness principles. Data were elicited through semi-structured interviews with three groups of LA learners. Contrary to previous studies (on other phonological aspects), which argue that interference errors decrease over time, findings show that gemination is attested across all groups of LA learners and persists even among advanced learners. Results show that interface phenomena involving more than one phonological level pose a great challenge to second language learners.