Pope Francis has travelled to eastern Cuba to celebrate the second Mass of a trip that has earned him praise for aiding the Communist rulers' rapprochement with Washington, but has so far steered clear of overt politics.

He is the first Pope to visit Holguin, capital of the province where the Castro brothers, Raul and Fidel, grew up.

On nearly every street corner, posters welcoming the pontiff adorned doors and telephone poles, while bike-taxis and horse-drawn carriages traversed below the yellow-and-white flags of the Vatican, fluttering alongside Cuba's red, white, and blue.

Raul Castro's government hopes the 78-year-old Argentine pontiff will condemn the still-intact US economic embargo against Cuba before leaving on Tuesday.

Critics of the one-party state want support for dissidents, some of whom have been denied attendance at papal events.