The Interior Ministry is considering a new legalization campaign for the estimated 300,000 illegal immigrants living in the country, officials said yesterday. The head of the Immigration Policy Institute (IPI), Alexandros Zavos, said some 600,000 people have joined past legalization campaigns. He was speaking ahead of an IPI conference on Monday on immigration management. Zavos said 250,000 of the people who have joined the process hold valid residence permits, while another 350,000 have applied for renewal of their documents. Red tape and understaffing have led to huge backlogs in the process. The IPI chief said ministry officials are studying the question of a new legalization drive. On the one hand, Zavos said, illegal immigrants boost the black economy, which is bad for economic growth, but a new legalization bid might attract a new wave of economic migrants.