Manchester City Council and the University of Manchester have agreed in principle to have a joint director for the Whitworth Art Gallery and Manchester Art Gallery.
Maria Balshaw, the existing director of the university's Whitworth Gallery on Oxford Road, will extend her role to manage Manchester Art Gallery when Moira Stevenson, the current Art Gallery director, retires.
The council said the new joint post will realise significant benefits for the two galleries in terms of the contribution they can make to the cultural life of the city through the sharing of academic research; the coherence of artistic vision for Manchester and the combined strength of their complementary collections.
Sir Richard Leese, leader of Manchester City Council, said: "Manchester Art Gallery has always been at the heart of our city's cultural ambitions and I believe this collaboration will bring real benefits to Manchester.
"This innovative arrangement will assist Manchester to realise its ambitions to become a world-class cultural city with a world-renowned university. We believe there are significant social and economic benefits to having such a vibrant artistic scene and this development will ensure we not only safeguard, but significantly enhance the city's cultural reputation."
Work is due to start in September on doubling the size of the public space, adding 4,000 sq ft of display area, at the university's Whitworth Art Gallery.
Designed by McInnes Usher McKnight Architects, the £12m project was given £8m Heritage Lottery Fund cash towards its development.
Completion is scheduled for autumn 2013.