The link also has a further link to the video of Benedict XVI's announcement
Declaratio
Dear Brothers,
I have convoked you to this Consistory, not only for the three canonizations,
but also to communicate to you a decision of great importance for the life of
the Church. After having repeatedly examined my conscience before God, I have
come to the certainty that my strengths, due to an advanced age, are no longer
suited to an adequate exercise of the Petrine ministry. I am well aware
that this ministry, due to its essential spiritual nature, must be carried out
not only with words and deeds, but no less with prayer and suffering. However,
in today’s world, subject to so many rapid changes and shaken by questions of
deep relevance for the life of faith, in order to govern the barque of Saint Peter
and proclaim the Gospel, both strength of mind and body are necessary, strength
which in the last few months, has deteriorated in me to the extent that I have
had to recognize my incapacity to adequately fulfill the ministry entrusted to
me. For this reason, and well aware of the seriousness of this act, with full
freedom I declare that I renounce the ministry of Bishop of Rome, Successor of
Saint Peter, entrusted to me by the Cardinals on 19 April 2005, in such a way,
that as from 28 February 2013, at 20:00 hours, the See of Rome, the See of Saint
Peter, will be vacant and a Conclave to elect the new Supreme Pontiff will have
to be convoked by those whose competence it is.
Dear Brothers, I thank you most sincerely for all the love and work with which
you have supported me in my ministry and I ask pardon for all my defects. And
now, let us entrust the Holy Church to the care of Our Supreme Pastor, Our Lord
Jesus Christ, and implore his holy Mother Mary, so that she may assist the
Cardinal Fathers with her maternal solicitude, in electing a new Supreme
Pontiff. With regard to myself, I wish to also devotedly serve the Holy Church
of God in the future through a life dedicated to prayer.
From the Vatican, 10 February 2013
BENEDICTUS PP XVI