(Adds background on PYD, close ties with PKK)

WASHINGTON, Oct 16 (Reuters) - A U.S. State Department official held direct talks for the first time over the weekend with the main Syrian Kurdish political party as the United States builds a coalition against Islamic State militants, a State Department official said on Thursday.

"We have for some time had conversations through intermediaries with the PYD (Kurdish Democratic Union Party). We have engaged over the course of just last weekend with the PYD," State Department spokeswoman Jen Psaki told a briefing.

Psaki said the meeting involved a State Department official and took place outside the region.

The PYD has close ties to the PKK, a Turkish Kurdish party that waged a militant campaign for Kurdish rights and has threatened to abandon a peace process with Turkey in response to the current attack on the Syrian town of Kobani by Islamic State militants.

The PKK is considered a terrorist group by Turkey, the European Union and the United States.

Turkish warplanes were reported on Tuesday to have attacked Kurdish rebel targets in southeast Turkey after the army said it had been attacked by the PKK, risking reigniting a three-decade conflict that killed 40,000 people before a cease-fire was declared two years ago. (Reporting by David Alexander; Editing by Sandra Maler)

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