Exclusive: Russia close to cutting oil output due to drone attacks, sources say

• Pipeline monopoly Transneft is restricting oil storage - sources
• Warns oil firms it may accept less oil - sources
• Ukraine steps up attacks on Russian ports, refineries
• Transneft describes the news as 'fake'

LONDON, Sept 16 (Reuters) - Russia's oil pipeline monopoly Transneft (TRNF_p.MM) ,has warned producers they may have to cut output following Ukraine's drone attacks on critical export ports and refineries, three industry sources said on Tuesday.

In a statement on its website, Transneft described the news as "fake" and part of the West's "information war" against Russia.