Sergey Kovalev's team are optimistic a deal can be agreed to fight Saul 'Canelo' Alvarez in November, but a catchweight is not on the table in talks.
The Russian light-heavyweight, the reigning WBO champion, is the front runner to become the next opponent for Mexican star 'Canelo', who is targeting a world title in a fourth weight division.
Terms could not be agreed in time for Kovalev to face Alvarez in September, which meant 'Krusher' instead defended his belt with an 11th round stoppage win over Britain's Anthony Yarde, but negotiations have resumed over a bout on November 2.
When asked if there was optimism over an agreement, Kathy Duva, CEO of Main Events who promote Kovalev, told Sky Sports: "Yes, possibly."
But Duva ruled out any discussion about Kovalev meeting Canelo at a different weight, with the 36-year-old having held a world title on three occasions during a hugely successful campaign at 175lbs.
Kovalev had confirmed before the Yarde fight that significant financial reward was available for a clash with 'Canelo' and had hoped that victory would pave the way for a deal to be reached.
"Yes, we had an offer," he said. "The offer was a substantial one.
"My primary task is to defend the title. If the fight is still interesting for Canelo, then okay.
"This fight gives us an opportunity to fight with Canelo later on."