VATICAN CITY: Pope Benedict XVI on Saturday promised top Vatican officials he would remain in "spiritual proximity" with them even after he resigns next week, at the end of a week-long spiritual retreat in the Vatican.

The pope also told members of the Roman Curia -- the government of the Church -- that the beauty of God's creation "is constantly contradicted by the evil of this world, by suffering and by corruption."

"It is as if evil constantly wants to sully creation to contradict God and render his truth and his beauty unrecognisable," the pope said.

He also thanked his aides for their assistance.

"I would like to thank all of you and not only for this week but for the past eight years in which you have shared the burden of the Petrine ministry with great competence, affection, love and faith.

"This gratitude will stay with me and even though our external visible communion is coming to an end, there remains a spiritual proximity, there remains a profound communion in prayer," he said.

The pontiff's spiritual retreat -- a period of prayer in his Apostolic Palace in the Vatican -- began on Sunday during a period of penitence in the Christian calendar ahead of Easter celebrations.

Tens of thousands of faithful are expected in St Peter's Square on Sunday when Benedict will recite his last weekly prayers and again on Wednesday when he will hold his final general audience.

The pope has said he will resign on Thursday -- the first pope to do so since the Middle Ages -- because he no longer has the strength of body and mind to carry out his duties in the modern world.