A charitable foundation has donated £500,000 to the new Library of Birmingham.
The Wolfson Foundation said the money would "help to provide world-class library facilities in the heart of one of the UK's major cities".
The 10-storey building, which it is estimated will cost nearly £190m, will replace the city's Central Library which was built in the 1970s.
The new library is set to open on 3 September.
The 10-storey building will boast an outdoor amphitheatre, a theatre, recording studio and free access to the National Film Archive.
The Wolfson Foundation said awarding the grant was a "strong statement" about the value of public libraries at a time they faced financial pressures.
Paul Ramsbottom, the foundation's chief executive, said: "Public libraries continue to play a crucial role in British society.
"In backing this excellent project, we hope that other funders might join us in supporting high quality initiatives at public libraries at a time of acute funding pressure for these great institutions.
"The Library of Birmingham will help to show the future shape of public libraries at a time of debate about their future role."
The Library of Birmingham Trust said it was "enormously grateful" for the generous support from the foundation.