* Ecuadorean leader under pressure for austerity measures
* Quito reforming economy in line with $4.2 bln IMF loan
* Fuel subsidy elimination triggered violent protests
* President Moreno stays firm, hundreds arrested
By Alexandra Valencia
QUITO, Oct 5 (Reuters) - Ecuadorean indigenous and union organizations kept protests going on Saturday and promised no let-up in their push to overturn austerity measures by President Lenin Moreno's government that have convulsed the nation for three days.
Demonstrations had been turning violent and shaping into a major challenge for Moreno, who won election in 2017 and has set his oil-producing nation on a centrist track after years of socialist rule under predecessor Rafael Correa.
But he got a reprieve on Friday when transport unions called off their strike after paralyzing roads for two days in opposition to the end of fuel subsidies.
Indigenous groups, however, continued on Saturday to block some roads around the Andean nation of 17 million people.
"The indigenous movement is mobilizing indefinitely in the whole country," Jaime Vargas, president of the CONAIE umbrella indigenous group, told Reuters.
"With or without jail, our resolve is firm."
Moreno, 66, has declared a two-month state of emergency and authorities have arrested 379 people after protesters set up burning barricades and hurled stones at police on Thursday and Friday during Ecuador's worst unrest for years.
Struggling with a large foreign debt and fiscal deficit, Moreno's government recently reached a three-year, $4.2 billion loan deal with the International Monetary Fund (IMF), contingent on belt-tightening economic reforms.
As well as ending fuel subsidies, the government is reducing the state workforce and planning some privatizations. Moreno says the fuel subsidies, in place for four decades, had distorted the economy and cost $60 billion.
"The Ecuadorean people are indignant at this package, which is a prize for businessmen and bankers, to comply with the IMF's recipe," said Mesias Tatamuez, head of the Workers' United Front umbrella union, adding there would be a national strike on Wednesday.
Despite such militancy in other sectors, taxi and bus services were gradually returning on Saturday.
It was unclear why the transport unions called off their strike, though leaders said they were satisfied the government had heard their complaints. Officials have promised a revision of fare tariffs to compensate for fuel price rises.
Moreno's popularity has sunk to below 30% compared with above 70% after his 2017 election, but he has the support of the business elite, the military appears loyal, and the political opposition is weak.
However, Ecuador has a history of volatility and sudden government changes: protests toppled three presidents in the decade before Correa took power in 2007.
Moreno, who uses a wheelchair after a 1998 shooting during a robbery that left him paraplegic, has promised a firm hand, and various transport leaders were rounded up in recent days.
Dozens of police officers have been hurt in the unrest.
Ecuador hopes to save about $1.5 billion a year from ending fuel subsidies. Along with tax reforms, the government would benefit by about $2.27 billion.
Moreno's government has improved relations with the West and reached its loan deal with the IMF in February, dependent on "structural measures".
Correa calls Moreno, his one-time protege and vice-president, a "traitor".
(Reporting by Alexandra Valencia in Quito; Additional reporting by Jose Llangari in Quito and Yury Garcia in Guayaquil; Writing by Andrew Cawthorne; Editing by Daniel Wallis)