LIMA, June 5 (Reuters) - Three legislators have quit President Ollanta Humala's Gana Peru party and more departures are possible as his crackdown on anti-mining protests and drift to the right erode his working majority in Congress.
The departing lawmakers on Tuesday accused Humala of spurning traditional allies on the left, courting big business and - most importantly - using force instead of mediation to quell vexing social conflicts over the spoils of mineral wealth.
Widespread conflicts over mineral resources threaten to delay some of the $50 billion in investments Peru has lined up for a sector that drives 60 percent of exports in one of Latin America's fastest-growing economies.
The president's far-left father, Isaac Humala, known for ornery comments and conspiracy theories, has called his son a sellout and warned that his presidency will be a failure.
The defections left Humala's party with 43 of 130 seats in Congress. Though Humala has relied on 20 seats from the Peru Posible party for a working majority, he will now have to look to the right-wing party of former President Alberto Fujimori for help in passing bills.
Humala won the presidency a year ago by shedding his hard-line image and recasting himself as a moderate leftist who could please foreign investors and spread the country's growing wealth to help the poor. Critics say he has abandoned the left.
"Promises made during the electoral campaign have been systematically ignored by the government," Javier Diez Canseco, one of the three dissident lawmakers, said in Congress.
Political analyst Fernando Tuesta said more defections were likely.
"There will be more departures in the future if the government loses the political capital to manage severe social conflicts," he said in a column in the newspaper La Republica.
Despite the party's turmoil, Humala is still the most popular Peruvian president in decades, with an approval rating of more than 50 percent in a country where his predecessors plumbed lows of less than 10 percent in polls.
The economy is growing 6 percent a year, inflation is low, and the government says it is investing in poor rural areas that were overlooked in a decade-long boom. Public investments are on track to rise by 30 percent this year and social welfare spending by 60 percent.
Relying on votes from Fujimori's party would draw criticism from the left, but since taking office Humala has repeatedly said he has abandoned any political ideologies to try to lead as a pragmatist.
Critics say the former military officer is too quick to rely on authoritarian tactics and has criminalized protests. His government has arrested local political heads for leading rallies against mines owned or planned by global miners Xstrata and Newmont.
Prime Minister Oscar Valdes, also a former military officer, has blamed far-left ideologues for fomenting the protests, and some of those leftist leaders are widely expected to make their own presidential bids in 2016.
Humala took office in July 2011, urging mediation to calm hundreds of disputes nationwide over the spoils of natural resources. Those efforts have averted some clashes with police who were sent in to clear roadblocks set by protesters.
But at least 10 people have died in disputes over natural resources under his watch. Similar clashes killed at least 174 during the tenure of Humala's predecessor, Alan Garcia.