It is not clear who is speaking in verses 1 and 2. In verse 1, two possibilities are that Yahweh tells the people of Israel to arise and state their case, or that Micah tells Yahweh to arise and state his case. In verse 2, two possibilities are that Yahweh is speaking to the mountains or that Micah is speaking to the mountains. The ULB has arranged the quote marks in a way that indicates that in verse 1, Yahweh tells his people to state their case, and in verse 2 Yahweh speaks to the mountains.
Yahweh says this to the people of Israel. He speaks as if he, his people, and the mountains and the hills were in court and as if the mountains and hills could hear what his people would say. (See: [[rc://en/ta/man/jit/figs-personification]])
Possible meanings are 1) Yahweh is telling his people to say what they think he has done wrong to them, or 2) Yahweh is telling his people to answer the accusation he will make against them.