Delek said in a report on production and financial performance the second quarter was the first time it started generating revenue from the Tamar natural gas field.
It said it started production at Tamar in March. The company estimates the field holds as much as 10 trillion cubic feet of natural gas.
"We are very pleased that we have finally started to realize the potential and began to recognize the revenues from the Tamar project," Delek's Chief Executive Officer Asaf Bartfield said in a Wednesday statement.
The company said second quarter revenue from oil and natural gas sales increased 54 percent in the second quarter year-on-year to $147.9 million in part because of Tamar.
The Energy Information Administration, the analytical division within the U.S. Energy Department, said in a report last week "regional security problems, territorial disputes, and macroeconomic uncertainty" could hinder developments in the Mediterranean.
Delek said it was analyzing production options for Leviathan, a discovery off the northern coast said to contain 19 trillion cubic feet of natural gas. Leviathan could start commercial production by 2016.