US first lady Melania Trump stepped off Air Force One in Riyadh on Saturday conservatively dressed in long sleeves and pants, to conform to the strict dress code Saudi Arabia enforces for its female citizens. One thing was missing: a headscarf.

Donald Trump’s daughter, Ivanka, an assistant to her father who is accompanying him on his trip, also did not cover her head.

Under the kingdom’s strict dress code for women, most female visitors are required to wear a loose black robe, known as an abaya, in public. Most women in Saudi Arabia also cover their hair and face with a veil known as the niqab. But covering one’s head is not required for foreigners.

Nevertheless, the issue had potential to cause embarrassment for Trump, whose long trail of Twitter messages often comes back to haunt him. Two years ago, he tweeted his displeasure over Michelle Obama’s decision to appear bare-headed in the kingdom.

“Many people are saying it was wonderful that Mrs Obama refused to wear a scarf in Saudi Arabia, but they were insulted. We have enuf enemies,” he tweeted, using a short-hand spelling for “enough”.