Caracas (AFP) - The leftist party of Venezuelan President Nicolas Maduro Tuesday challenged the election of 22 opposition lawmakers in this month's landmark polls, according to opposition leaders who slammed a "procedural coup."

The opposition coalition MUD won a resounding victory in the December 6 legislative vote, ending 16 years of leftist majority in the oil-rich but troubled nation.

Jesus Torrealba, spokesman for the MUD, told a press conference that Maduro's United Socialist Party of Venezuela (PSUV) had filed a challenge against 22 incoming deputies before the Supreme Court.

"These are not representatives of the MUD, they are representatives of the people," Torrealba said of the lawmakers targeted.

With 112 of 167 seats in the new National Assembly, the opposition would be able to call a referendum, launch constitutional reforms, replace senior judges and even take measures to try to depose Maduro.

But if the challenge goes ahead it could prevent the lawmakers concerned from being sworn in as planned on January 5, leaving the opposition short of the crucial two-thirds majority.

"We say without hesitation that what we are facing here is an attempted procedural coup against the will of the people expressed clearly and decisively on December 6," Torrealba said.

He said he had informed the Organization of American States and the European Union of the development.

Analysts have warned of a tough political struggle ahead after Venezuela's election, which dealt a dramatic blow to Maduro and the "revolution" launched in 1999 by his late predecessor Hugo Chavez.