President Joe Biden and his Chinese counterpart Xi Jinping spoke on the phone in “candid” conversations on Thursday, with Xi reportedly cautioning Biden against “playing with fire” in regards to Taiwan.

The virtual conference, which lasted more than two hours, occurred as Beijing and Washington ran the risk of escalating their standoff over the self-governing island, which China views as a part of its territory.

According to the state-run Xinhua news agency, Xi was quoted as saying to Biden in reference to Taiwan, “Those who play with fire will inevitably get burned,” using the same terminology he did when they spoke last November.

Xi told Biden, “I hope the US side fully understands that.”