NEW YORK (Reuters) - Iran's President Hassan Rouhani said on Thursday that American companies were welcome to invest in Iran.

"Iran has never had problems with American companies to invest in Iran ... the nuclear deal has paved the ground for all foreign investors and companies to invest in Iran," Rouhani told a news conference on the sidelines of the annual U.N. gathering of world leaders.

(Reporting by Michelle Nichols; Editing by Chris Reese)