WikiLeaks founder Julian Assange has said it could take at least seven years to study all secret materials archived by his whistleblower website.

Speaking in a video interview with the Russian Reporter magazine, Assange said that the leaked documents were just a small portion of the materials that he has, and more "waves" should be expected in the next month-and-a-half.

The 39-year-old Australian activist said WikiLeaks "only scratched the surface" and it could take as long as seven years to thoroughly study the documents that shed light on many important events in many countries.

The recent publication of secret documents caused media stir, but world leaders and diplomats unanimously downplayed the impact of the information leak on international relations.

Assange said their reaction was predictable, but these facts would attract more and more public attention in the future, leaving less room for "plausible denial."

Russian Reporter is a partner of the WikiLeaks website in Russia.