ATHENS — The Chinese embassy in Athens lashed out against U.S. Ambassador Kimberly Guilfoyle on Wednesday over her recent criticism of Beijing’s investments in Greece.

Guilfoyle’s comments were a “malicious slander” against Sino-Greek trade relations and a “serious interference in Greek internal affairs,” an embassy spokesperson said in a written statement.

Last week Guilfoyle said China’s state ownership of the Port of Piraeus, Greece’s largest such facility, was “unfortunate” and suggested it could be circumvented. “Something could be worked out, whether you pursue a path of enhancing output in other areas or perhaps that Piraeus could be for sale,” she opined.

The Chinese embassy was unimpressed. “The port of Piraeus belongs to the Greek people; it is not a tool for undermining regional prosperity and stability, and under no circumstances should it fall victim to geopolitical confrontation,” the statement read.

“At a time when the port of Piraeus is undergoing rapid development, the US with self-serving intentions, is encouraging Greece to terminate its contractual obligations and sell the port — this practice is a typical example of imposing its own thinking on others and reveals a mindset that attempts to undermine stability.”

China invested heavily in debt-ridden Greece during the country’s lengthy economic crisis, a decade-long saga that started in 2009, with the goal of making it a hub for Chinese exports. At the time, companies from other Western countries were turning away from Athens, spooked by its financial woes and infamous bureaucracy.

Cosco, China’s state-owned shipping company, secured a majority stake in the Port of Piraeus in 2016. Beijing intended that Piraeus become a key part — the so-called dragon’s head — of its Belt and Road global infrastructure project.

“The port of Piraeus was handed over to the Chinese during the financial crisis in Greece, as they were the only ones who submitted a bid,” Greek Foreign Ministry spokesperson Lana Zochiou said during a Tuesday briefing in Athens. “Greece respects the agreements that have been conducted in the past.”

Guilfoyle, a one-time conservative pundit on U.S.-based network Fox News, suggested Beijing’s current influence might be offset by increasing American investment in other infrastructure projects.

Indeed, Athens is accelerating plans to develop a new port in Elefsina, a U.S.-backed project that officials say could serve as a counterweight to China’s presence in Piraeus. The idea was discussed on Tuesday at a meeting between Guilfoyle and Greek Development Minister Takis Theodorikakos, after which Athens moved to implement the plan.

“We look forward to seeing Elefsina Port evolve into a logistics hub for the region,” Guilfoyle said after the meeting.