Nokia's Chief Executive Stephen Elop said tougher competition was the main reason behind the fall in sales of regular mobile phones.

Nokia reported earlier that its mobile phone sales in the first quarter slumped 31 percent from a year earlier to 1.59 billion euros, a sharper drop than the 14 percent decline that analysts expected in a Reuters poll.

(Reporting by Ritsuko Ando; Editing by Tom Pfeiffer)