WASHINGTON, Aug 21 (Reuters) - The Trump administration

on Thursday issued more Iran-related sanctions, targeting 13

entities based in Hong Kong, China, the United Arab Emirates and

the Marshall Islands, as well as eight vessels, the U.S.

Treasury Department said.

The measures cover Greek national Antonios Margaritis and

his network of companies and vessels that Treasury said was

involved in transporting Iranian oil exports in violation of

sanctions.

Treasury also designated Ares Shipping Limited in Hong Kong,

Comford Management in the Marshall Islands and Hong Kong

Hangshun Shipping Limited in Hong Kong.

Designated crude oil tankers include Panama-flagged vessels

Adeline G and Kongm, and Lafit under the flag of Sao Tome and

Principe.

The State Department separately said it imposed sanctions on

two China-based operators of oil-related terminals and storage.

It said they handled imports of Iranian oil aboard tankers

previously targeted by U.S. sanctions.

The firms were identified as Qingdao Port Haiye

Dongjiakou Oil Products Co in Shandong province and Yangshan

Shengang International Petroleum Storage and Transportation Co

in Zhejiang province.

A person at Qingdao Port Haiye Dongjiakou Oil Products Co

who answered a phone call told Reuters they were not aware of

the sanction and declined to comment.

State-owned Qingdao Port International, the

major shareholder of Haiye, did not respond to a request for

comment.

Yangshan Shengang International Petroleum Storage and

Transportation did not immediately respond to a request for

comment.

Iran suspended talks with Washington aimed at curbing the

Islamic Republic's nuclear ambitions after the U.S. and Israel

struck its nuclear sites in June. Iran denies any intent to

develop atomic bombs.

Iran's top diplomat said on Wednesday that the moment for

"effective" nuclear talks with the United States has not yet

arrived, adding that Iran would not completely cut off

cooperation with the United Nations nuclear watchdog.