Greece has "seriously neglected" its obligations to control external borders, the European Commission has said in a draft report, BBC News reports.

The assessment, made on a visit last November, describes serious deficiencies in Greek management.

Greece is required to control its borders as part of the passport-free Schengen accord and has been given three months to improve the situation.

More than 850,000 migrants and refugees arrived in Greece last year alone.

A further 44,000 have reached the Greek islands since the start of 2016, mostly arriving on Lesbos, Samos and Chios from the Turkish mainland.

The draft report cites failings in registering, fingerprinting and checking the identities of migrants, BBC says.

If the Greek government is unable to make improvements, the European Commission says it will consider giving other Schengen states the right to enforce temporary border controls at Europe's internal frontiers.