China has signed an agreement to join the World Health Organization-led COVAX facility, a vaccine project that the United Nation’s health body and several other countries are working on to ensure poorer countries have access to COVID-19 vaccine as soon as it is available.

China was reluctant to support the project, toeing the path of Russia and the United States. However, China’s decision to sign the agreement means a boost to COVAX as it is the biggest economy to grace the project so far.

Hua Chunying, Chinese Foreign ministry spokeswoman said in a statement posted on Twitter that the decision was “an important step to uphold the concept of a shared community of health for all and to honor its commitment to turn COVID-19 vaccines into a global good.”

How poor countries would access COVID-19 vaccine became a serious question in the Wake of the world’s push for a vaccine and the US government’s preorder of about 1.6 billion vaccines.

To curtail the fear about poor nations lacking access to the vaccines, the WHO started the Global Access Facility (COVAX) in collaboration with the Coalition for Epidemic Preparedness Innovations (CEPI), GAVI and the Vaccine Alliance. The aim is to deliver some two billion doses of vaccine around the world by the end of 2021.

Considering the financial resources required, the WHO is wooing rich nations to join the project. Teaming up with 92 low and middle-income economies means there will be enough funds for the project.

COVAX’ goal is to produce at least three safe and effective vaccines that will be made available to all parties in the scheme.

However, some of the rich countries expected to grace the project, including the United States and Russia are working on their own vaccines. Russia has already developed the Sputnik, a vaccine it released in early September and is planning to distribute to some poor nations. While on the other hand, the US president is acting on his “America first” mantra, which means the US government will focus on the American when the vaccine becomes available.

The Chinese government has been testing experimental vaccines made by some companies on hundreds of people in China, as they get to the final phase of their clinical trials.

Against this backdrop, WHO’s invitation to rich nations to support COVAX has been unanswered by the rich economies.

The UN Secretary-General Antonio Guterres, earlier this month, reiterated his call for additional $15 billion funding for the project by the end of the year.

COVAX is like Noah’s ark that will save the world from the deluge of COVID-19, but that pretty much depends on meeting the funding target: The reason why the WHO wants everybody on board.

“The race for vaccines is a collaboration, not a contest,” said WHO Director General Tedros Adhanom Ghebreyesus. “This is not charity. We sink or swim together.”

The WHO is working to meet a late 2021 target for the distribution of the vaccines, spurring the push for countries to sign up. So far, more than 150 countries, which represent 64 percent of the world, have signed up on the COVAX project. But out of the 150 countries, only 64 are higher income countries.

China signing the agreement becomes imperative as it is seen to fill the leadership gap left by the United States. The White House said this month that the US would not join, partly because it has secured vaccines for itself and because of its fallout with the WHO, who Trump is not willing to work with for now.

The game changer pointed out by Washington Post would be if the vaccines the US and the rest of rich economies are counting on fail to be viable. It may force them and other indecisive countries to embrace COVAX.

But while it is encouraging to see China signed up, as it would more likely inspire other countries to do the same, challenges remain. The World Health Organization still falls far short of its overall goal with COVAX, particularly funding, which has been hampered by the economic strains of coronavirus and the US’ decision to stop funding the WHO.