The leaders of Azerbaijan and Iran are expected to discuss the Caspian status. RIA Novosti has learnt in the Azerbaijanian president's staff that Geidar Aliyev will visit Iran on May 18th-20th. The sides are to highlight a broad spectrum of bilateral relations and regional problems. A number of agreements will be signed on co-operation between the two countries in trade and economic, financial, border, customs, education, culture and sports areas. According to Izzatullah Jalali, press secretary of the Iranian embassy in Baku, 11 out of the 12 documents are ready for signing. The political declaration of the Iranian and Azerbaijanian presidents will seal the sides' principled positions on the Caspian legal status. This issue is expected to feature prominently at the meetings between Aliyev and political and spiritual leaders of Iran. The Iranian side insists on the condominium principle providing for common use of the Caspian resources by the five littoral states, or equal 20-percent shares for each country concerned. Azerbaijan prefers sectional division of the seabed, with common use of its surface and the waters. Iran regards its 1921 treaties with the Soviet Russia and the 1940 treaty with the Soviet Union as the legal basis for exploring the sea resources until the status is determined. Azerbaijanian Foreign Minister Vilayat Guliyev, on this part, has claimed that the treaties are out-of-date, at a session of the special working group for the Caspian in Baku. On Thursday, May 16th, the Caspian issues were discussed at Aliyev's meeting with Steve Mann, the special representative of the US President and the US Secretary of State for the Caspian. Earlier, Aliyev's visit to Iran was repeatedly postponed.