RIYADH- Saudi Arabia's Crown Prince Mohammed bin Salman arrived in Paris on Sunday at the start of a European tour after three weeks in the United States, where he pitched for investments and support against arch-rival Iran.

France's foreign minister, Jean-Yves Le Drian, who worked closely with Prince Mohammed as defence minister in the previous French government, greeted him at the airport, the Saudi foreign ministry said on Twitter.

Saudi officials said separately that Prince Mohammed, who serves as defence minister and also controls economic and energy policy for the world's top oil exporter, would head to Spain later in the week.

He is set to meet French President Emmanual Macron on Tuesday. On the agenda for his two-day stay in Paris are the conflicts in Yemen, Syria and the Iran nuclear deal. He will also attend cultural events and an economic forum.

A tourism project between Paris and Riyadh is likely to be announced, but he is not expected to clinch any mega-deals.

Activists were planning protests on Sunday. Macron is under growing pressure from lawmakers and rights groups over France's weapons sales to the Saudi-led coalition fighting Iran-backed Houthi rebels in Yemen.

(Reporting By Stephen Kalin Editing by Raissa Kasolowsky, Larry King) ((stephen.kalin@tr.com; +966554282201; Reuters Messaging: stephen.kalin.thomsonreuters.com@reuters.net))