* Russia looking at range of responses to U.S. sanctions
* U.S., EU imposed sanctions on Russian, Ukrainian officials
* Suggests response may be found in Iran talks (Adds details, quotes)
By Thomas Grove
MOSCOW, March 19 (Reuters) - Moscow will respond in kind to U.S. sanctions imposed on Russian officials over the Crimea dispute and is considering other steps if Washington escalates tensions, Deputy Foreign Minister Sergei Ryabkov said on Wednesday.
On Monday, the United States and the EU announced sanctions on a handful of officials from Russia and Ukraine accused of involvement in Moscow's seizure of Ukraine's Crimea region, most of whose 2 million residents are ethnic Russians.
Washington has threatened further sanctions while Russian lawmakers raced to ratify a treaty making Crimea part of Russia by the end of the week.
"We are looking at a broad range of responsive measures. They can be identical measures regarding certain lists of American officials - not necessarily representatives of the administration ... who have influenced American policies," Ryabkov was quoted as saying by Interfax.
"There is also the possibility of passing asymmetrical measures, that means steps which, let's say ... won't go unnoticed in Washington," he said.
Russian Foreign Minister Sergei Lavrov has called the sanctions "unacceptable." But some of the Russians included on the list of individuals have scoffed at the measures which would freeze their assets in the United States.
Ryabkov gave few details on what form those measures could take but suggested that six-party talks over Iran's nuclear programme could provide a means of response.
"Moscow would not want to use these talks as an element of raising the diplomatic stakes," he said.
"But if we are forced, we will follow here a path of responsive measures because in the end the historical importance of what has happened in the last days and weeks regarding the ... reunification of Crimea with Russia is incomparable to what we are doing regarding Iran."
Failure of the six world powers to come to an agreement with Iran at the negotiating table may have domestic political implications for U.S. President Barack Obama who has been criticised for his softer stance on Iran.
Ryabkov was present at talks held on Wednesday over the future of an Iranian nuclear reactor, which the West sees as a possible source of plutonium bombs. The two sides appeared to reach no agreements and participants have promised to meet again on April 7-9.
Russia has closer ties with Iran than the Western powers have and has been seen to use its relationship with the Islamic Republic in the past as a lever of influence over the West. (Reporting by Thomas Grove; Editing by Sonya Hepinstall and Phil Berlowitz)