SINGAPORE — Pope Francis arrived in Singapore on Wednesday from East Timor, on the final leg of an ambitious 12-day journey across Southeast Asia and Oceania.

The Aero Dili flight carrying the pope and his entourage arrived in the city-state for a two-night visit that will include a speech to political authorities and a Mass at the National Stadium, which the Vatican expects to draw some 55,000 people.

The pope will also hold private meetings with President Tharman Shanmugaratnam, Prime…