Venezuela said on Thursday the United States had banned President Nicolas Maduro's jet from flying through U.S. airspace over Puerto Rico en route to a state visit to China.
Maduro is due in Beijing this weekend for bilateral talks. China has become a major lender to his government, and Chinese firms are heavily involved in the OPEC nation's oil industry.
But Foreign Minister Elias Jaua said a flight plan filed by Venezuela that would have routed Maduro's plane over Puerto Rico had been rejected by U.S. authorities.
"We received the information from the U.S. authorities that they have denied us the overflight through U.S. airspace," Jaua told reporters. "We denounce it as yet more U.S. aggression against the Bolivarian Government of Venezuela."
Jaua said Washington had no right to deny airspace to any presidential plane, but that the move would not stop Maduro from visiting China.
"There's no valid argument to deny this overflight," he said. The government was studying other routes, he added, "but we reserve the right to take whatever measures we have to if the U.S. government and its aviation authorities don't rectify this new assault on Venezuela's sovereignty."
Maduro has often clashed with Washington since winning an election in April that was triggered by the death from cancer of his mentor, the late socialist leader Hugo Chavez.
In July, Venezuela said it was ending efforts to improve ties with Washington after the Obama administration's nominee for envoy to the United Nations vowed to oppose what she called a crackdown on civil society in the "repressive" country.
The latest diplomatic spat is reminiscent of this year's incident when Bolivia said France, Spain, Italy and Portugal denied their airspace to President Evo Morales' jet, apparently on suspicion the aircraft might have been carrying fugitive U.S. intelligence agency contractor Edward Snowden out of Russia.
Days after that, Venezuela's Maduro became the world's first leader to offer asylum to Snowden, who is wanted by Washington for disclosing details of secret surveillance programs.