Minimum period of ILR before Naturalisation application?

Do I have to spend at least 1 year on ILR before applying for Naturalisation? I thought this is one of the mandatory requirements and there is not scope of negotiation. Recently one of my friends got his ILR after being on work permit for 5 years form an immigration solicitor. He has been told by this firm that he could apply for Naturalisation after having been on ILR for about 6months if he is able to prove strong ties to UK and they have in fact volunteered to do the application for him. Has any body heard of this rule?

TC wrote:Do I have to spend at least 1 year on ILR before applying for Naturalisation? I thought this is one of the mandatory requirements and there is not scope of negotiation. Recently one of my friends got his ILR after being on work permit for 5 years form an immigration solicitor. He has been told by this firm that he could apply for Naturalisation after having been on ILR for about 6months if he is able to prove strong ties to UK and they have in fact volunteered to do the application for him. Has any body heard of this rule?

This is not true, unless you are married to British Citizen you have to wait 12 months after ILR to apply for British citizenship.