The United Nations emergency relief coordinator on Wednesday sent his condolences to the Chinese government and people over the 7.1-magnitude earthquake in northwestern China and praised China's immediate and effective response to the disaster.

John Holmes, the UN under-secretary-general for humanitarian affairs,made the remarks in his phone conversation with Li Baodong, the Chinese permanent representative to the United Nations.

It is convinced that the Chinese people, under the strong leadership of the Chinese government, will surely complete their relief work and post-quake reconstruction in Qinghai Province, which was struck by the massive tremor early Wednesday, Holmes said.

The UN system, including the UN humanitarian agency, is ready to offer all necessary assistance to China at any time at the request of the Chinese government, he said.

Li thanked Holmes for his condolences and offer of help, saying Chinese President Hu Jintao and Premier Wen Jiabao on Wednesday urged all-out efforts to save lives and provide assistance to people affected by the deadly earthquake.

He added that the relief work was going on in a prompt and effective manner.

The death toll from the quake rose to 617 as of 9:00 a.m. on Thursday local time (0100 GMT), according to local quake-relief headquarters. There were 313 people missing and 9,110 people injured, including 970 who suffered serious injuries.