In his will, Pope Francis asked for simple tomb.

The Vatican on Tuesday morning released photographs of Pope Francis laid out in state in the Casa Marta chapel following his death on Monday at the age of 88.

The move comes as the College of Cardinals gathers to select a date for the funeral of the late pontiff who decreed in his will that he be buried in a simple underground tomb in the papal basilica of Santa Maria Maggiore, or St Mary Major, in the Esquilino area of Rome.

The funeral, whose date may be announced later on Tuesday, is set to take place this weekend.

In the meantime, the body of Pope Francis is expected to be laid in state in St Peter's Basilica as early as Wednesday.

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In his final testament, Francis specified that he wanted to be buried "in the ground, without particular decoration" but with the inscription of his papal name in Latin: Franciscus.

The will expressed the pope's wish to be buried in Rome, not at St Peter's in the Vatican, and revealed that Francis had arranged for an unnamed benefactor to cover the costs of his burial.

In addition the Vatican released a death certificate showing that the pope died following a cerebral stroke that led to a coma and irreversible heart failure.

Photo Vatican Media