Users will be notified of the update by the 15th of May, and if the terms are not accepted then they may no longer have access to sending or receiving messages.
It is likely that the call and notification functionality will still be possible despite not agreeing to the new terms, however it is not known how long WhatsApp will allow this.
Many users backlashed at the company when the initial announcement was made during January, this was due to concerns over the data being shared with Facebook.
However, In a further statement WhatsApp confirmed that the update was predominantly enabling payments to business in app.
Some information is already shared with Facebook through the messaging service, such as the IP address of users and in-app purchases.
However, the EU and UK have different privacy laws that prohibit WhatsApp sharing that information.