Facebook is asking some new users to provide the password to their email account.

The move has alarmed security experts, who warn it could encourage users to engage in "risky" behaviour and increase their chances of being hacked.

The social network also appears to be accessing these users' contacts without asking for permission.

The company now says it is discontinuing this login tool, though it didn't give a timeframe.

Facebook asks some new users to provide the social network with the password to their email accounts, a move that security experts say has concerning security implications — and that could teach people to engage in "risky" behaviour online.