China has finally congratulated Joe Biden on his projected win in the US presidential election, breaking a frosty period of silence. "We respect the choice of the American people. We extend congratulations to Mr Biden and Ms Harris," a foreign ministry spokesman said on Friday. The China-US relationship is crucial to both sides, and the wider world. Tensions have soared in recent times, over trade, espionage and the pandemic. Russia is yet to offer well wishes. Four years ago, the Russian leader Vladimir Putin was among the first to congratulate Donald Trump on his election victory, but there has been no tweet, telegram or phone call to Mr Biden this time. "We believe the correct thing to do would be to wait for the official election result," Kremlin spokesman Dmitry Peskov told reporters. Mr Biden has taken calls from a string of global leaders in recent days. Congratulations began to pour in from Saturday, when US networks projected the result and he declared victory. President Trump has continued to make unsubstantiated allegations of voter fraud without providing clear evidence. On Thursday, a group of federal and state election officials directly rebutted such claims, saying the vote was "the most secure in American history".