Nigeria Liquefied Natural Gas Ltd (NLNG) has approached international banks for a potential $2 billion secured financing, banking sources close to the deal said. NLNG — a consortium of state-owned Nigerian National Petroleum Corp, Royal Dutch Shell, Total and ENI — is expected to raise the deal by the end of the year, the bankers added.

“They have the distinction of having probably the best looking and most transparent balance sheet in sub-Saharan Africa, so while the absence of a credit rating will limit their options, nobody sees great challenges in the way of such a target,” one of the bankers said.

The main challenge will be pricing, because NLNG has requested quotes for tenors between 7 and 10 years, the bankers said.

“The fly in this ointment is that in our post-credit crisis world, tenor has become a much bigger hurdle than it used to be because now banks dig in hard on liquidity premiums, which increase fairly exponentially with tenor,” the banker said. NLNG could not immediately be reached for comment.NLNG says it supplies 10 percent of the world’s liquefied natural gas.