The semi-official Straits Exchange Foundation, in a letter to its Beijing counterpart, sent the island's sympathy to quake victims and said it was willing to provide any necessary help.
Monday's 6.8 magnitude quake was the deadliest to hit Xinjiang since the Communists took power in 1949.
Taiwan, which sits on a volcanic bedrock, has also suffered devastating tremors in the past.
In 1999, a massive 7.6 earthquake struck the island and killed more than 2,400 people. Taipei had then rejected a similar aid offer from Beijing, accusing its giant neighbour of mixing politics with relief efforts.
Taiwan and China have been bitter political rivals since a civil war ended in 1949. Beijing views the self-governing island as a breakaway province that must be brought to the fold, by force if necessary.
The Straits Exchange Foundation and its counterpart, the Association for Relations Across the Taiwan Strait, handle negotiations in the absence of official contacts.
- Reuters - Thomson Reuters Foundation
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