GENEVA, Feb. 3 (Xinhua) -- World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus said on Monday that he sees "no reason" for unnecessary interference with international travel and trade during the novel coronavirus outbreak.

Addressing the 146th session of the WHO Executive Board meeting that kicked off here on Monday, Tedros called on all countries to implement evidence-based measures to tackle the virus, reaffirming that the WHO stands ready to provide advice to countries on how to manage the outbreak.

Last week, Tedros declared the novel coronavirus outbreak a Public Health Emergency of International Concern (PHEIC).

Outside China, there are 151 confirmed cases in 23 countries, and one death, which was reported from the Philippines on Sunday, Tedros said.

"If it weren't for China's efforts, the number of cases outside China would have been very much higher," he reiterated.

"The decision to declare a PHEIC was taken primarily because of the signs of human-to-human transmission outside China, and our concern of what might happen if the virus were to spread in a country with a weaker health system," he added.

Tedros spoke highly again of the Chinese leadership's commitment in fighting the epidemic.

The WHO chief further explained that the current effort should remain focused on fighting the virus at the epicenter and the source, which could slow down and minimize the spread of the virus to other countries.

While showing confidence in keeping the outbreak under control, Tedros also warned, "don't make a mistake, it can get even worse. But if we give it our best, the outcome could be even better."