St. Paul was head of the Gentile Churches; St. Peter was head of the Jewish section only.

The Catholic Answers

If so, you are in a great difficulty. If the Church was thus divided and St. Paul was head of the Gentile section, where is St. Paul’s successor to-day? We have the successors of St. Peter in the Popes, and the present Pope is head of the Church with over 400 millions of subjects, the vast majority of them Gentiles. In any case, St. Paul again and again addressed the Jews in their Synagogues, and St. Peter certainly ministered to the Gentiles in his turn, above all as Bishop of Rome.

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty