Shares in the Italian lender have been bearing the brunt of market losses since the beginning of the year, and one local newspaper on Wednesday reported rumours that Fintech may be selling.

The source said those rumours were unfounded, adding that Fintech, which is controlled by Mexican billionaire David Martinez, had an unchanged 4.5 percent holding in the Tuscan bank.

"We are not selling," the source said, speaking on condition of anonymity.

Monte dei Paschi shares closed up 1.6 percent at 0.9430 euros on Wednesday.

(Reporting by Silvia Ognibene, writing by Silvia Aloisi)