* Dollar index bounces from 1-yr low in early European trade
* C.bank sets yuan mid-point at highest in nearly four months
* United States puts new duty on Chinese-made tyres
SHANGHAI, Sept 14 (Reuters) - The yuan ended nearly flat against the dollar on Monday after the U.S. currency hovered around one-year lows against a basket of currencies, but trade tensions between China and the United States checked gains.
The U.S. dollar index rose 0.58 percent to 77.054 in early European trade on Monday late afternoon, rebounding from its one-year low of 76.457 hit late last week, undermined by falling Treasury yields.
Persistent talk about Asian central banks diversifying from U.S. dollars to other currencies and assets, including gold, also combined to damp the U.S. dollar.
Spot yuan closed at 6.8289 on Monday, almost unchanged from Friday's close of 6.8290.
Before trade began, the Chinese central bank fixed the yuan's daily mid-point at 6.8280 versus the dollar, the reference rate's highest level since May 18 and almost unchanged from Friday's 6.8282.
"The central bank raised the mid-point slightly higher than 6.8300 as the dollar continues declining," said a dealer at an Asian bank in China. "But we still expect the yuan to remain stable in the near term because the government still faces pressure from exporters."
On Monday, China decried a U.S. decision to impose an added duty on Chinese-made tyres, saying the move sent a dangerous protectionist signal before a G20 summit and could stoke reactions impeding global recovery.
U.S. President Barack Obama slapped additional duties on tyre imports from China on Friday in Washington, in what White House spokesman Robert Gibbs said was meant "to remedy the clear disruption to the U.S. tyre industry" from cheap Chinese imports.
But dealers said the new duty on Chinese-made tyres was having a limited impact on the spot yuan trade although trade tensions at a time when China's exports are already sluggish, hurt market sentiment.
Offshore, benchmark one-year dollar/yuan non-deliverable forwards (NDFs) rose slightly to 6.7395 bid late on Monday, compared with Friday's close of 6.7230.
Twelve-month yuan appreciation implied by NDFs, which moves inversely with the forwards, fell slightly to 1.31 percent measured from the Chinese central bank's daily mid-point, compared with 1.56 percent implied at Friday's close. (Reporting by Shanghai Newsroom; Editing by Chris Lewis)