Cloud migration transforms company's data, applications and services to (or between) one or more other Cloud environments. Enterprises are increasingly migrating their IT infrastructures to Cloud, given the appeal of (pay-per-use) elastic resources. Yet, existing IT infrastructures are complex, heterogeneous and dynamic ecosystems. As a result, there is no single standardized process to seamlessly manage migration at enterprise scale, and often significant level of manual intervention is required, both in reasoning about migration and during its execution. This paper presents a system that automates the process of migration to Cloud. It embeds a Metric-FF Artificial Intelligence (AI) planning algorithm to dynamically assemble migration plans based on the properties of source and target environments, as well as available migration tooling. The paper describes the challenges in migration planning, AI domain design for migration. This work demonstrates that the system provides an effective and scalable solution to generating plans based on the source environment of 700 servers, and varying size of the migration service requests.