CAIRO, July 18 (Reuters) - Saudi Arabia and Turkey signed a number of memorandums of understanding in many fields including energy, direct investments and defence, Saudi state news agency SPA reported early on Tuesday.

Turkey's President Tayyip Erdogan and Saudi Crown Prince Mohammed bin Salman, the kingdom's de facto ruler, witnessed the signing ceremony of the bilateral agreements between the two countries, SPA said.

Saudi Arabia signed two contracts with Turkish defence firm Baykar to buy drones "with the aim of enhancing the readiness of the Kingdom's armed forces and bolstering its defense and manufacturing capabilities," Saudi Defence Minister Prince Khalid bin Salman said in a tweet on Tuesday,

The two countries also signed a defence cooperation plan, the minister added.

Erdogan met the crown prince late Monday night, SPA added.

He had arrived in the kingdom earlier on Monday for the first stop of a Gulf tour with "high hopes" for investment and finance as Turkey looks to ease budget strains, chronic inflation and a weakening currency.

Erdogan's Gulf tour, which also includes Qatar and the United Arab Emirates, is due to conclude on July 19. (Reporting by Enas Alashray and Yomna Ehab; Editing by Jamie Freed and Lincoln Feast)