The Saudi-backed group announced earlier in the day it was "postponing" participation in the UN-mediated negotiations that resumed late last week.
"We will stay until at least the end of the week. If there is some progress, some signs that things will be settled, we will continue. If not, of course we will leave," Makhous said.
He stressed that the opposition delegation would return to the negotiating table "once there is real progress, any day, at any moment."
"We are not moving away from the political process. These are two different things. We will continue the process, but we will abstain from the talks," Makhous said.
He stressed that the Saudi-backed group does not put forward any preconditions in its decision to postpone the proximity talks with the Syrian government delegation.
"Our demand is to implement the [UN] Security Council decision," Makhous added.
"Our decisions have been essentially completely unanimous. I am not saying 100 percent, but the vast majority completely agrees, there is no disagreement between people who represent the civil opposition or the military," Makhous said.
"Naturally, the people who are fighting on the ground are more demanding. But we still maintain the same line," the Saudi-backed opposition group’s spokesman added.