The Vatican on Wednesday voiced its "concern" over President Donald Trump's executive orders to build a wall on the US-Mexican border and impose a travel ban on nationals from seven Muslim-majority countries.

"Naturally, there is concern," the Holy See's No. 3, Monsignor Angelo Becciu, said on the Catholic TV channel TV2000. "(...) We are builders of bridges, far less of walls, and all Christians should emphatically reaffirm this message."