BAGHDAD — Vice President Mike Pence made an unexpected visit to Iraq on Saturday, arriving as protests aimed at toppling the Iraqi leadership and changing the political system continued to roil the country.

Mr. Pence made two stops: He landed with the permission of the Iraqi government at Al Asad Air Base in Iraq’s western desert, where many of the American troops are billeted while they train and assist the Iraqi forces fighting the remains of the Islamic State. He then flew to Erbil, the capital of Iraqi Kurdistan.

Mr. Pence received a classified briefing at the air base, from which American Special Forces had launched the operation in Syria last month that led to the death of the Islamic State leader, Abu Bakr al-Baghdadi.

He then spoke by phone with Prime Minister Adil Abdul Mehdi but did not meet with him, according to the Mr. Mehdi’s office. In a statement, his office said the two men “discussed the latest developments in Iraq and the Iraqi government efforts at reform in response to the demonstrators’ demands.”