The mountain brings forth a mouse

Too little, too late / The mountain has brought forth a mouse (Prov.)


Fare il parto della montagna

Fare come la montagna che partorì un topolino


Meanings
Fig.: it refers to great promises and labors that produce little and, sometimes, ridiculous results

Examples
After weeks of massacres of innocent people, the worldwide relief agency decided to send someone to investigate, which was too little, too late
Dopo settimane di stragi di civili innocenti, l'ONU ha deciso di mandare qualcuno in ispezione. È il classico esempio della montagna che partorisce un topolino

Origin
Its origin can be traced back to ancient Greece, when Phedrus wrote in his fable “The mountain in labor” (Fables Ph IV, 24) about people who make great promises and then accomplish nothing:
“A Mountain was in labor, sending forth dreadful groans, and there was in the districts the highest expectation. But, in the end, it brought forth a mouse.
This is designed for you, who, when you have threatened great things, produce nothing”
The same concept was in La Fontaine's fable La montagne qui accouche (V, 10).
Horace writes in his Ars Poetica (138-139): "Parturiunt montes, nascetur ridiculus mus".