The current CEO has taken a leave of absence following medical advice and is expected to return at some stage soon.
However, if his return is delayed, Mr Roberts, who previously worked at Barclays, would step in. Current interim CEO Tim Tookey is leaving Lloyds in February 2012 to take up another position.
Win Bischoff, chairman at Lloyds, said: âThe board is pleased that Antonio is making good progress and we are looking forward to his return at the end of the year.
âHowever, we recognise it is important that we formalise the contingency arrangements if Antonioâs return is delayed.â
Mr Horta-Osorio joined Lloyds in March 2011 from Santanderâs British division.
Meanwhile, Nathan Bostock, chief risk officer at the Royal Bank of Scotland, has decided to remain with RBS rather than joining Lloyds as the bank originally announced earlier in the year.
By Jim Ottewill