(Reuters) -UnitedHealth Group said on Monday it has advanced payments of over $2 billion so far to provide assistance to healthcare providers, financially affected following a cybersecurity attack on its technology unit, Change Healthcare.

The company said it will start releasing its medical claims software on Monday and it will become available to "thousands of customers" over the next several days.

Change Healthcare, which was hit by a cyberattack on Feb. 21, is a vital lynchpin in the system for making and clearing insurance claims as it processes about 50% of medical claims in the United States for around 900,000 physicians, 33,000 pharmacies, 5,500 hospitals and 600 laboratories.

UnitedHealth last week restored its payments processing and pharmacy network services after days of disruption following the cyberattack.

The company said on Monday it will continue restoration of remaining services until all customers have been connected.

UnitedHealth said it has suspended paperwork required to get approval for insurance coverage for most outpatient services, as well as review of inpatient admissions for government-backed Medicare Advantage plans to help those impacted.

(Reporting by Bhanvi Satija and Sriparna Roy in Bengaluru; Editing by Shinjini Ganguli)