Mr Drakeford told a press conference that eight of the 10 new coronavirus cases in Wales are believed to be from the Delta variant.
“In just a few weeks the Delta variant entered Wales and quickly spread across the country,” he said.
“There is a pattern of sustained and accelerated transmission, not only in North and South East Wales, but in all parts of the country.
“This means that we are, once again, facing a serious public health situation. Our science advisers believe the UK is now at the pre-peak stage of a third wave of this pandemic.
‘Wales could be two to three weeks behind what is happening in England and Scotland, where tens of thousands of cases have been confirmed, where there is widespread transmission and reports of admissions to the hospital increases as well. “
Drakeford said Nicola Sturgeon and Boris Johnson have suspended plans to ease restrictions on coronaviruses due to the Delta variant.
“Today I have to announce that we will do the same in Wales,” he added.
The Welsh government will suspend further easing of coronavirus restrictions for four weeks to allow more people to get vaccinated, Mr Drakeford told reporters.
“A four week delay could help cut the maximum number of daily hospitalizations in half,” said Drakeford.
Delta variant infections in the UK have jumped 78% in just one week, according to the latest data from Public Health England (PHE).
The number of confirmed Covid-19 cases involving this more transmissible variant – also known as the Indian variant – has increased from 33,630 to 75,953 in seven days, with general coronavirus infections now at their highest level in the Kingdom -United since mid-February.
Additional reports by the PA