Reasonably easy. I would encourage you to prepare beforehand. I had a phone interview that lasted for around 15 minutes. asked me my reasons to apply for the position. What will i bring to the team. where do i see myself in 5 years time. it is easy to keep talking on and on but keep your answers to the point and structured. Infact use SMART technique to answer any questions. Finally do not panic and do not get nervous if you dont know how to answer a question. Just ask for a minute to think over it. Best of luck