TORONTO -- Endeavour Mining Corp. is walking away from its attempt to buy Centamin PLC.

The companies had been in merger talks since late last year regarding a possible deal after Toronto-listed Endeavour made a stock-swap proposal to acquire Centamin.

The proposal valued Centamin at roughly $2.5 billion at the time.

However, Endeavour now says it does not plan to make a firm offer and therefore the merger discussions have been terminated.

Endeavour chief executive Sebastien de Montessus says the company was not confident that proceeding with a firm offer would have been in the best interests of Endeavour shareholders.

Centamin's principal asset is the Sukari gold mine in Egypt, but the company also has projects in Burkina Faso and Cote d'Ivoire.