Process for the preparation of an aluminium phosphate-containing composition wherein an aluminium source is converted partly to aluminium phosphate using a phosphorus-containing compound and partly to (i) an anionic clay and/or a Al-MII mixed metal (hydr)oxide using a divalent metal (MII) source, (ii) an aluminosilicate using a silicon source, and/or (iii) a MII- aluminosilicate using both a divalent metal source and a silicon source.