WASHINGTON, May 22 (Reuters) -

Turkey stopped purchasing Iranian oil as of May as U.S. waivers granted last November to eight buyers expired, and will continue to abide by Washington's demand that it halt all imports of crude oil from the Islamic Republic, a senior Turkish official said on Wednesday.

"We are not getting any oil from Iran now," said the official, who spoke on condition of anonymity. "We were one of the eight countries getting an exception from those sanctions, and now we are ready to abide by them," he said.

The U.S. decision to fully reimpose sanctions on Iranian oil ended a six-month reprieve for Turkey and seven other big importers as Washington stepped up attempts to isolate Iran and choke off its oil revenues.

Reuters on Monday reported that no tankers loaded in Iran have arrived at Turkish ports so far in this month, according to Refinitiv tracking data.

The data shows that Turkey began trimming its Iranian imports as early as March. Analysts said it has replaced the oil from Iran with oil from Iraq, Russia and Kazakhstan.

Turkey's largest oil refiner Tupras had pressed Washington for an extension of the import waiver before the May 1 expiration, according to a person familiar with the talks, adding that when it was not granted, the company made it clear it would halt all imports from Iran.

But the official added that Ankara did not agree with U.S. sanctions policy on Iran. "We don't believe in sanctions, but as a strategic ally we respect the U.S. decision ..." We don't believe isolation of Iran will be helpful," he said.