POTENTIAL CONFLICT.

Narrative

APCH CTL ASKED IF WE WANTED A RIVER VISUAL TO RWY 13. WE RESPONDED YES. THE ILS 13 AND RIVER VISUAL WERE REVIEWED AND BRIEFED. APCH CTL CLRED US RIVER VISUAL TO 13 TO MAINTAIN 3000 FT. THEY SAID TO MAINTAIN 3000 UNTIL N OF THE PARK AND THEY CITED TFC AT 2 O'CLOCK TO US AT EITHER 2000 OR 2500 FT. WE ACKNOWLEDGED THE MAINTAIN 3000 BUT WE DID NOT HAVE THE TFC. THE TFC RESPONDED TO APCH THAT THEY WERE DSNDING TO 1500 FT. APCH CTL MADE NO FURTHER MENTION OF THE TFC TO US. WE CONFIGURED TO FLAPS 20 AND SLOWED TO 180 KTS IN PREPARATION FOR DSCNT FROM 3000 WHEN WE PASSED THE PARK. WE WERE TRANSFERRED TO LA GUARDIA TWR. OUT ON FINAL INSIDE THE MARKER AT 2000 FT; THE TCASII ADVISORY IMMEDIATELY SOUNDED WITH AN ALERT RESOLUTION THAT COMMANDED A LEVEL OFF AND CLB. I IMMEDIATELY ARRESTED MY DSCNT AND ACTUALLY CLBED BACK TO 2200 FT BEFORE THE TCASII ALERT WAS RESOLVED. WE WERE TOO HIGH THEN FOR A VISUAL APCH SO WE WERE CLRED BY TWR FOR A VISUAL TO 22 WITH L TURNS TO BASE. WHEN TWR WAS ADVISED OF THE ALERT WITH TCASII; THEY ACKNOWLEDGED THAT IT WAS THE 1500 FT TFC PREVIOUSLY RPTED TO US AND SINCE IT WAS BEING WORKED BY APCH THEY DID NOT CONSIDER IT A TFC CONFLICT. DURING THE LEVEL OFF AND SUBSEQUENT CLB I SAW TFC PASSING BELOW AND TO OUR R. I ASSUMED THAT AS LONG AS WE HAD MAINTAINED 3000 FT UNTIL N OF THE PARK THAT THERE WOULD NOT BE A TFC CONFLICT. I FEEL THAT EXCEPT FOR THE TCASII ADVISORY THIS COULD HAVE POSSIBLY BEEN AT BEST A CLOSE TFC CONFLICT. I FEEL THAT WE WERE CORRECT IN RESPONDING TO THE TCASII ADVISORY BUT SHOULD HAVE EITHER REQUESTED CONFIRMATION OF SEPARATION FROM THE TWR OR APCH OF THE RPTED TFC. IT WOULD ALSO HELPED HAD THERE BEEN MORE COM BTWN TWR AND APCH ON THE STATUS OF OUR TFC. THE BASIC LESSON HERE IS NEVER ASSUME. IN THE ABSENCE OF FURTHER RPTS FROM TWR OR APCH ON THE STATUS OF OUR TFC WE SHOULD HAVE AGGRESSIVELY SOUGHT THIS INFO AND REQUESTED TFC SEPARATION FROM THE CTLING AGENCIES.