Narrative:

Enroute from saez north bound at FL340. Contacted maiqeta svzm fir controller for authorization to climb to FL380. Told to stand by. Controller called back and said to climb to FL380. I read back clearance. First officer (first officer) selected 380 in MCP. I looked at map display on my panel and saw a TCAS target 900 feet above me approximately 20 miles out. I told the first officer not to climb and reset 340 in window. I contacted maiqueta and told them in no uncertain terms that I am not climbing and will maintain FL340 due to traffic ahead. Controller responded back stand by. I put all my landing lights on to illuminate my aircraft as did the opposing aircraft. The aircraft at 350 was aircraft Y south bound on airway. I think I heard aircraft Y come on guard and say 'aircraft X; this is aircraft Y' on front of you. In a moment aircraft Y passed directly over top of us as the controller in what seemed to be a panic voice said 'aircraft X maintaintain FL340 do not climb!' I responded back calmly that we did not climb and are level at FL340. A few minutes later he re-cleared us to climb to FL380. I can only assume that the controller was not aware of our position relative to the opposing aircraft 1000 feet above us; coming directly at us. Communications is so poor in those sectors that instructions often get misinterpreted from both the controller and the pilots. When I asked if we were radar contact I never got a response. I can't exactly answer why this occurred but I can tell you 100% why a mid-air collision did not occur. Proper sa (situational awareness) and using the tools and training provided to our pilots contributed to the safe outcome of this flight. Offsetting from the airway would definitely add another layer of protection. Using max external illumination for climbs and descents in south american airspace where communications is marginal at best.

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Original NASA ASRS Text

Title: Air Carrier Captain reported ATC error when issued a climb clearance; into opposite direction traffic 900 feet above; and stayed at present altitude to avoid conflict.

Narrative: Enroute from SAEZ north bound at FL340. Contacted MAIQETA SVZM FIR controller for authorization to climb to FL380. Told to stand by. Controller called back and said to climb to FL380. I read back clearance. FO (First Officer) selected 380 in MCP. I looked at map display on my panel and saw a TCAS target 900 feet above me approximately 20 miles out. I told the FO not to climb and reset 340 in window. I contacted MAIQUETA and told them in no uncertain terms that I am not climbing and will maintain FL340 due to traffic ahead. Controller responded back stand by. I put all my landing lights on to illuminate my aircraft as did the opposing aircraft. The aircraft at 350 was Aircraft Y south bound on airway. I think I heard Aircraft Y come on guard and say 'Aircraft X; this is Aircraft Y' on front of you. In a moment Aircraft Y passed directly over top of us as the controller in what seemed to be a panic voice said 'AIRCRAFT X MAINTAINTAIN FL340 DO NOT CLIMB!' I responded back calmly that we did not climb and are level at FL340. A few minutes later he re-cleared us to climb to FL380. I can only assume that the controller was not aware of our position relative to the opposing aircraft 1000 feet above us; coming directly at us. Communications is so poor in those sectors that instructions often get misinterpreted from both the controller and the pilots. When I asked if we were radar contact I never got a response. I can't exactly answer why this occurred but I can tell you 100% why a mid-air collision did not occur. Proper SA (Situational Awareness) and using the tools and training provided to our pilots contributed to the safe outcome of this flight. Offsetting from the airway would definitely add another layer of protection. Using max external illumination for climbs and descents in South American airspace where communications is marginal at best.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.