Urea arylation with aryl halides in the presence of catalyst precursor Pd(2)dba(3)-CHCl3/Xantphos and Cs2CO3 in dioxane at 100degreesC affords symmetrical N,N-diarylureas in 64-92% yield. With the same catalytic system the reaction between N-phenylurea and aryl bromides containing electron-withdrawing substituents in the para-position provided N-aryl-N'-phenylureas in 64-91% yields.