Turkey imported 1.174 million tons, about 270,000 barrels per day, of Iranian crude oil in March, according to official trade data on the Turkish Statistical Institute web site, obtained by Reuters following a request. A Turkish industry official said April imports fell back to a more normal 140,000 bpd and would remain at about the same level in May.
The March figures represent the highest monthly purchase of Iranian crude by Turkey since July 2011 and are almost triple the 401,349 tons, 100,000 bpd, imported in February. The imports also reflect a 90 percent jump from March 2011.
Turkish Energy Minister Taner Yildiz said at the end of March that the country would diversify its oil supplies.
But quarterly trade figures highlight Iran's strong dominance in Turkey's crude imports.
The data shows Iran accounted for 2.44 million tons, 193,000 bpd, or more than half of the 4.416 million tons, or 350,000 bpd, of crude Turkey imported in the first three months of this year.
Its second biggest supplier, Iraq, trailed far behind with 568,326 tons, 45,000 bpd, in the same period. Last year, Iran provided more than half of Turkey's total crude oil imports at just over 18 million tons.
Trade between Turkey and Iran has risen sharply over the past decade, leading to Turkey being regarded as a possible weak link in the international sanctions against Iran.
Washington has threatened to impose sanctions on companies from countries that do not back its efforts to isolate Iran.