Western Cape Premier Alan Winde says a 21-day lockdown announced by President Cyril Ramaphosa on Monday might cause some anxiety, but assured residents the province would work closely with the government to ensure their safety.

In a statement released shortly after Ramaphosa's announcement, Winde welcomed the president's announcement on Monday of stricter measures to curb Covid-19 in South Africa as part of a national lockdown set to begin on Thursday.

"What we have seen globally over the past few months has been unprecedented in recent history," Winde said.

"These announcements are likely to cause a lot of anxiety but I want to reassure residents that we will be working closely with the national government to ensure that the announcements made tonight are effectively implemented to ensure that our residents remain safe and healthy."

He said he would be meeting with his team on Tuesday to ensure they were able to provide clarity about the situation as soon as possible.

"There is no need to panic. These measures have been taken with the best interests of all South Africans in mind."

Winde reiterated shops would remain open and people would be able to access food and medication easily.

"There is absolutely no need to resort to panic buying and hoarding. We have met with big retailers who have assured us of sufficient supplies.

"Over the next few days, we will be evaluating where food security risks lie, and addressing these."

He said given South Africa's history, these restrictions would impact many hardworking people, but emphasised all South Africans must work together to ensure the goals of the lockdown were met.

"In a country where personal freedom was hard-won, and where people have had to work hard to build careers and livelihoods, a shutdown comes with a high price.

"But the lives of the people of this country and this province are worth far more than this and we must all work together now to ensure that this lockdown achieves the goals it has set out to achieve - to reduce the impact of the virus and flatten the curve of infection," Winde added.