Perez said Petroecuador is even willing to lease its infrastructure, such as pipelines or storage tanks.

One broker suggested a lump sum of up to $4.5 million could be made for an LR2 loading in US Gulf to ship to China, compared with $2.5 million carrying clean products.

"Operators are going to face higher loading prices for their gasoil, as well as, freight cost," a trader said.

The PAS "defines general requirements that apply to all 0.50 mass % sulfur fuels and confirms the applicability of ISO 8217 for those fuels."

"Singapore and Fujairah [bunker] markets will move independently after 2020 depending on the fundamentals of each port,"a trader said.