Turkey said on March 30 that it would cut imports of oil from Iran by 20 percent from last year's quantities, ceding to US pressure to reduce purchases.
Iran is Turkey's largest crude oil supplier, followed by Iraq. Last year, Iran provided more than half of Turkey's total crude oil imports at just over 18 million tonnes.
Turkey accounted for 7 percent of Iran's crude oil exports in 2011, according to the US Energy Information Administration, on par with Italy or nearly half the level of EU imports combined.
Turkish state refiner Tüpraş took around 5.3 million barrels of Iranian crude in April, or around 177,000 barrels per day (bpd), according to shipping agency data from its two import terminals Tutunciftlik and Aliaga.
While Turkey has reduced imports by 100,000 bpd compared with March, it is a reduction from an unusually high month. April imports are only marginally below its 2011 average of 200,000 bpd.
The volume is also higher than the 140,000 bpd April figure a Turkish industry official said was imported last week and is not yet the 20 percent cut promised by the Turkish government.
The April figure could even be slightly higher taking into account cargoes coming from the Egyptian port of Sidi Kerir but the origins of the crude could not be verified because the terminal exports Saudi, Iraqi, Egyptian as well as Iranian crude.
Turkey imported 1.174 million tonnes, about 270,000 barrels per day, of Iranian crude oil in March, the highest monthly purchase since July 2011.
Tüpraş maximised its March contract with Iran's state oil company NIOC but the data also likely includes some February cargoes, which were delayed into the next month. February imports were unusually low at 100,000 bpd.
"Any potential discrepancy could be explained as a matter of timing," Cuneyt Kazokoglu, analyst at FG Energy, "We think some of Turkey's March imports of are actually cargoes exported out of Iran in February and because of this time-lag data for the same month from different sources could vary."
Most European refiners have progressively stopped lifting Iranian crude ahead of the impending EU oil embargo due to take effect from 1 July. Imports have fallen to around 350,000 bpd in April down from 740,000 bpd, trade data compiled by Reuters showed.
Some refiners have bent to US pressure while others were forced to stop due to banking and shipping obstacles. Asian refiners have also started reducing their imports.
The EU and US widened sanctions at the start of the year on increased suspicions that Iran is trying to develop atomic bombs, while Iran insists its nuclear programme is solely for civilian purposes.