Issuing a statement the UNP leader said the number of COVID-19 linked deaths rose to 5,000 on the 7th of August while 20 days later deaths are nearing 8,000.
Wickremesighe said the Epidemiology Unit has stated that there have been late entries putting into question the statistics.
Wickremesinghe said there is a rapid spread of COVID-19 that must be prevented especially from people being impacted.
He claimed immediate action is to deal with those who are already infected, in order to prevent the rapid spread in order to reduce the number of those infected.
The former Premier said the government declared a ten day lockdown for this purpose, adding that according to medical advice this is not a sufficient period and another week to two weeks are required.
The UNP leader stated today we have reached a point where the damage caused by a lockdown is far less than the damage caused by not having a lockdown.
He claimed the remedy for this is to immediately go to the International Monetary Fund to seek assistance.
Wickremesinghe noted Sri Lanka has already received US $720 million from the IMF for the COVID control campaign.
Accordingly, the UNP leader recommended to the government, the President, the Prime Minister and the Cabinet of Ministers to extend the lockdown according to medical advice.