There are a few sources claiming he said this ("I actually stopped the Oslo Accords"), but all of those I found are rather left-wing. E.g. a 2012 opinion piece in Haaretz or a piece in Jewish Currents from the same year. To quote the latter:
Benjamin Netanyahu is a man who boasted on videotape, in 2001, “I actually stopped the Oslo Accords.”
So, did he actually say that?
I'm a bit skeptical because it's apparently not been more widely reported, although maybe it was just considered a politically unremarkable statement, I'm not sure. Netanyahu did formally negotiate the Wye River Memorandum, which Wikipedia describes as "aimed to resume the implementation of the 1995 Interim Agreement on the West Bank and the Gaza Strip (Oslo II Accord)". So him boasting about stopping the accords is perhaps not entirely congruent with that... Or maybe it is, given the word "resume"?!