The head of the World Health Organization (WHO) pleaded with rich countries on Monday to check before ordering additional coronavirus disease 2019 (Covid-19) vaccine shots for themselves whether that undermines efforts to get vaccine shots to poorer nations.

Wealthy nations have snapped up several billion vaccine doses while some countries in the developing world have little or none. European nations have given financial support to the United Nations-backed COVAX effort to get vaccines to the world’s most vulnerable people and are considering sharing some of their own doses — though they haven’t specified when.

On Friday, leaders of the Group of Seven (G-7) industrial powers said they would accelerate global vaccine development and deployment and support “affordable and equitable access to vaccines” and treatments for Covid-19. They cited a collective $7.5 billion from the G-7 to UN-backed efforts.

WHO Director-General Tedros Adhanom Ghebreyesus thanked the G-7 countries for their “significant” pledges. But he said after talks Monday with German President Frank-Walter Steinmeier that “even if you have the money, if you cannot use the money to buy vaccines … having the money doesn’t mean anything.”

He said some rich countries’ approaches to manufacturers to secure more vaccines are “affecting the deals with COVAX, and even the amount that was allocated for COVAX was reduced because of this.” He didn’t name those countries or give other details.

Tedros added that rich countries need to “cooperate in respecting the deals that COVAX did” and make sure before they seek more vaccines that their requests don’t undermine those deals.

“But I don’t think they’re asking that question,” he said.

Tedros, who has previously warned that the world faces a “catastrophic moral failure” if Covid-19 vaccines are not distributed fairly, said he understands the political pressures leaders in high-income countries face.

They should, he added, tell voters that “the best way to protect you is not only to vaccinate you, but vaccinate the rest of the world, share the vaccine with the rest of the world.”

Tedros underlined the importance of using every opportunity to step up vaccine production “because with increased production, the pie is increased, then there is a better volume to share.”

“Otherwise, with shortages, sharing is difficult,” he said. “And that’s exactly what’s happening now.”

The 27-nation European Union is among the regions where authorities face pressure over a sluggish start to vaccination efforts. The bloc secured deals last week for millions of additional vaccines.