By Mitra Taj and Marco Aquino

LIMA (Reuters) - Peru fears Venezuela may be headed toward civil war as a political crisis deepens and its economy implodes under the rule of socialist Venezuelan President Nicolas Maduro, Peru's foreign minister told Reuters on Wednesday.

Speaking a day after summoning his counterparts from across the region to Lima to condemn the "rupture of democratic order" in Venezuela, Ricardo Luna said Maduro's support at home and abroad had shrunk as he seeks to consolidate power through the constituent assembly, a powerful new body run by the ruling Socialist Party loyalists.

Peru has been one of Venezuela's harshest critics since centrist President Pedro Pablo Kuczynski took office a year ago, replacing a former ally of late Venezuelan leader Hugo Chavez.

Luna called Maduro's accusation that Kuczynski is conspiring with U.S. President Donald Trump "absurd."

Peru's concern, he said, is the humanitarian crisis that has already sent waves of Venezuelan refugees to neighboring nations, including some 40,000 to Peru in the past six months.

"Our fear is that you really have a low-intensity civil war, which would produce a humanitarian crisis of great proportions," Luna said in an interview in his offices in Lima.

"It's not necessarily going to happen, and it's not easy to compare it to major crisis such as the one we have in Syria. But it is a large country. It's a complex situation. It's something that's been building in time," Luna said.

More than 125 people have died in clashes in Venezuela since the opposition began sustained protests in April. On Sunday, Venezuelan authorities quelled an attack on a military base by soldiers and armed civilians, killing two of them in a dramatic escalation of unrest.

Luna said Maduro's "autocracy" does not appear to have sufficient support among Venezuelans to hold on to power for several decades as Cuba's government has, and it may not be long before the oil-producing country's economy collapses completely.

"The last leg can last weeks, months, or even half a year. Not more than that," Luna said.

Peru is evaluating new ways to pressure Venezuela to enact democratic reforms, including expelling Venezuela's ambassador from Peru or reducing Peru's diplomatic presence in Venezuela, Luna said.

While Maduro might shrug off the Lima Declaration signed by 12 nations on Tuesday, including Canada, Brazil and Mexico, the collective condemnation sends a signal to the world that most in the region no longer sees Venezuela as a democracy, Luna said.

The new bloc plans to meet to discuss Venezuela again at the United Nations General Assembly.

(Reporting By Mitra Taj and Marco Aquino; Editing by Michael Perry)