Proclamation
Declaration
noun, verbal noun
You proclaim things by saying them. This is a proclamation or declaration.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
ポツダム宣言っていつだっけ？
When was the Potsdam Declaration?
ここに長きにわたった二国間の戦争が終結したことを宣言します。
We hereby declare that the long war between the two countries is over.
彼のお気に入りのアイドルが、年末に引退するって宣言したから、彼も他のファンもショックを受けちゃってるのよ。
His favorite idol shocked him and other fans by announcing that she will retire at the end of this year.