The Seleccao were held to a 3-3 draw by Israel last Friday and currently sit third in Group F with eight points from five games, trailing leaders Russia by four points.
"We have zero room for error from here on," the Real Madrid star was quoted as saying on the official website of the Portuguese Football Association.
Ronaldo will miss Tuesday's qualifier against Azerbaijan due to suspension, but he is keen to stay with the team as he feels his presence benefits the Seleccao.
"The easiest thing for me would have been to return to my club, but I said that I wanted to stay. I feel that my presence with the team is important," he explained.
He added, "I can still contribute something to the team even when I'm not playing. I'm a bit sad that I can't help the guys out there on the pitch, but I will encourage the team to give their all and get a good result."
Portugal head into Tuesday’s match without a win since September 2012.