Beijing - Surging inflation that helped trigger protests in Shanghai is prompting China's leaders to turn to a tool they long resisted: Speeding up the rise of the country's tightly controlled currency.

China’s leaders declared taming inflation their priority. But they suffered a setback in March, when a double-digit jump in food costs pushed inflation to a 32-month high of 5.4 percent. That was despite four interest rate hikes since October, curbs on bank lending and government orders to producers to hold down price increases.

How fast to let the yuan gain is a high-stakes balancing act. A stronger yuan could help ease inflation by making oil and other imports cheaper. But Beijing also worries that a rising yuan might hurt exports and lead to job losses and unrest.

"Policymakers have sent a clear message that currency appreciation will be used as a tool to counter imported inflation" due to near-record global prices for oil and other commodities, said Credit Agricole CIB economist Dariusz Kowalczyk.

At a Cabinet meeting this month, Premier Wen Jiabao said the government would "increase the flexibility of the yuan's exchange rate" to ease price pressures, the official Xinhua News Agency reported.

Economists blame China's inflation on the dual pressures of consumer demand that is outstripping food supplies and a bank lending boom they say Beijing allowed to run too long after it helped the country rebound quickly from the 2008 global crisis.

Attempts at price controls, subsidies for the poor and orders to local leaders to guarantee adequate vegetable supplies have had mixed results.

Beijing also is struggling to control an overheated economy that expanded by a rapid 9.7 percent in the first quarter of this year, barely slowing from the previous quarter despite Beijing's efforts to steer growth to a sustainable level after 2010's double-digit gains.

The World Bank is forecasting 9.3 percent growth this year, well above the 8 percent target announced by Wen in March.

"That growth is being generated by the same policies that are fueling inflation. So what looks like a great number applies to a very stressful economic situation," said Patrick Chovanec, an associate professor at Tsinghua University's School of Economics and Management in Beijing.

Beijing broke the yuan's direct link to the dollar in 2005 and allowed the currency to rise gradually after that. It was frozen again following the 2008 crisis to help Chinese exporters compete abroad after a plunge in global demand wiped out millions of factory jobs. Beijing promised more flexibility again last June but the US government says gains since then have been too small.

Analysts say even a faster rise for the yuan will be gradual — perhaps a 5 percent gain against the dollar this year instead of the 3 percent previously forecast. The yuan has risen about 1.5 percent this year, after gaining 3.6 percent in 2010.

Beijing also has resorted to the blunt tool of freezing prices of electricity and some other basic goods, but that is starting to backfire.

In a possible effort to deflect criticism, it has imposed fines on retailers who it said cheated shoppers by overstating the size of price cuts on discounted items.