Story highlights Other Western female leaders have visited Saudi Arabia without covering their heads

No law requires foreign women to wear a hijab

(CNN) British Prime Minister Theresa May drew the world's attention on Tuesday when she decided not to cover her hair during an official visit to Saudi Arabia.

May refused to follow a strict religious and cultural tradition. Women in Saudi Arabia, where Islam is the state religion, are expected to cover their heads.

Saudi women follow a conservative dress code in public. They wear a full-body garment called an abaya and cover their heads and hair with a hijab or a niqab, which has a slit for the eyes.

May is visiting Saudi Arabia as part of a tour of the Gulf Arab countries to promote post-Brexit trade deals. On Tuesday, she landed in Riyadh, where she met the crown prince.

The only other female British Prime Minister, Margaret Thatcher, met with King Fahd of Saudi Arabia in 1985. She wore a long dress and a hat during her visit.

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