TEGUCIGALPA, Honduras (AP) - The Honduran president vowed Thursday to ignore a Supreme Court ruling ordering him to reinstate the military chief he fired, escalating a showdown that has threatened the leftist leader’s hold on power.

President Manuel Zelaya’s attempt to hold a referendum Sunday on changing the constitution has pitted him against the country’s top courts, the attorney general, military leaders and even his own party, all of whom argue the vote is illegal.

But Zelaya has galvanized the support of labor leaders, farmers and civic organizations who hope constitutional reforms will give them a greater voice in a conservative country where 70 percent of the population is poor.

The crisis quickly ballooned when Zelaya fired Gen. Romeo Vasquez as head of the Joint Chiefs of Staff late Wednesday for refusing to support the referendum, which is intended to measure popular support for possible constitutional changes. Zelaya has not said what he wants, but critics accuse him of trying to extend presidential terms before his ends in January, like his ally Hugo Chavez did in Venezuela.

The Supreme court ordered Vasquez reinstated Thursday and warned Zelaya would face penal consequences if he does not respect the ruling.

"We will not obey the Supreme Court," Zelaya told more than 2,000 cheering supporters gathered in front of the presidential offices. "The court, which only imparts justice for the powerful, the rich and the bankers, only causes problems for democracy."