Regarding, as regards, in regard to, with regard to = in relation to ...

As regards, in regard to and with regard to are all standard compound prepositions. Thy are all very similar..

 Ex.:  With regard to your letter…
        In regard to the matter we debated this morning…        As regards temperament,  the two presidents are.....

Don´t use "to" after regarding

The following phrases can be used as "respecto de":

• Regarding the …
• As regards….
• With respect to
• In regard to…
• With regard to …