KIEV, May 3 - Ukraine and Russia will probably reach a deal by the end of September to amend their 2009 agreement, resulting in lower natural gas prices, Ukrainian Energy Minister Yuriy Boyko said.

The comment for the first time gives a timeframe for the deal and come days after Ukraine and Russia have begun formal negotiations on amending the 10-year agreement.

“I believe that we will make progress. This is not an easy process because it harbors huge interests of our countries,” Boyko said in an interview with Inter television aired on Saturday.