PhosCo (ASX:PHO) began exploration activities after identifying new targets at its Gasaat and Sekarna phosphate projects in Tunisia, according to a Wednesday Australian bourse filing.

It began diamond drilling at Gasaat to test priority new prospects to accelerate potential resource definition, as it seeks to to expand the existing mineral resource estimate.

It also began mapping and trenching at Sekarna to define the scout drilling program while a sighter metallurgical test work is planned to investigate the potential of the project to produce a saleable product.

The firm's shares rose past 8% on market close on Wednesday.