WARSAW: The Russian and Polish presidents hailed what they described as a new era of improved relations Monday, as they signed deals meant to deepen their countries' economic, political and cultural ties. Russian President Dmitry Medvedev and his Polish counterpart, Bronislaw Komorowski, oversaw the signings at the presidential palace in Warsaw. One accord signed is a broad declaration to deepen and diversify trade and economic cooperation far beyond a relationship that is now based mainly on Poland importing gas and oil from Russia. The declaration stresses the need to modernize the Russian economy and society.