Novel uracil substituted phenyl sulfamoyl carboxamides I and salts thereof, where A=oxygen or sulfur; X1=H, halogen, C1-C4-alkyl; X2=H, CN, CS—NH2, halogen, C1-C4-alkyl, C1-C4-haloalkyl; X3=H, CN, C1-C6-alkyl, C1-C6-alkoxyalkyl, C3-C7-cycloalkyl, C3-C6-alkenyl, C3-C6-alkynyl, optionally substituted benzyl; R1, R2=H, halogen, optionally substituted hydroxy, C1-C10-alkyl, C2-C10-alkenyl, C3-C10-alkynyl, C3-C7-cycloalkyl, phenyl, benzyl or C5-C7-cycloalkenyl, or R1+R2 together with the atom to which they are attached form a 3- to 7-membered heterocyclic ring; Q is selected from Q1 to Q40 as defined in the description. Use: As herbicides; for the desiccation/defoliation of plants.