Venezuelan President Hugo Chavez said Monday that reconciliation is impossible with Colombia's president as the two leaders traded stern warnings in an escalating diplomatic crisis that threatens trade ties between the South American neighbors.

Chavez said Sunday he is putting relations "in the freezer" after President Alvaro Uribe ended the Venezuelan leader's role mediating with Colombia's leftist rebels. That announcement drew a strong rebuke from Uribe, who said Chavez's actions suggest he wants to see a "terrorist government" run by leftist rebels in Bogota.

The spat is the bitterest yet between Chavez and the U.S.-allied Uribe, who in the past have sought to cultivate cordial ties despite their deep ideological differences.

It could have serious economic consequences. The two countries are major commercial partners, with $4.1 billion in trade last year, about two-thirds of that in Colombian exports to Venezuela.

Neither leader announced any concrete plan, but Chavez said economic relations will be hurt as a result of Uribe's actions, which he called "a spit in the face."

Relations with Colombia have reached their "most serious crisis," Chavez said in a televised interview early Monday. While diplomatic channels may remain open, he said, "not reconciliation because it's impossible now. When it reaches these levels between two heads of state, it's impossible."

"We'll have to wait for a new government in Colombia we can talk with," Chavez said on state television. "I hope it arrives sooner than later."

He said Venezuela will be on alert to potential military threats from Colombia as well.

Chavez has also declared he is freezing relations with Spain until its king apologizes.