US President Joe Biden announced Tuesday that all American adults will be eligible for COVID-19 vaccine by April 19.

Biden announced the new timetable after his visit to a vaccination site in Alexandria, Virginia, moving up his original deadline of May 1 by nearly two weeks.

Biden said that 150 million doses of COVID-19 vaccine have been administered within his first 75 days in office, in line with a stated goal of 200 million shots by his 100th day in office.

He urged Americans to continue to practice pandemic safety measures, saying the country is not "at the finish line yet" and may experience more "disease and misery" before July 4.

A few weeks ago, Biden called on states, tribes and territories to make all US adults eligible for vaccination no later than May 1.

Biden has stressed that while the country is now vaccinating a record number of Americans, the battle against COVID-19 is "far from won" as cases are once again on the rise.

The country has seen a rise in new cases in 27 states, including cases from new and emerging COVID-19 variants. Currently, the seven-day average of new COVID-19 cases is about 61,000 cases a day, a 10 percent increase over the previous period, according to the latest data of the US Centers for Disease Control and Prevention (CDC).

Biden has called on every governor, mayor and local leader to maintain -- and in some cases reinstate -- mask mandates.

Some states' governors have lifted requirements for masks and allowed businesses to reopen to full capacity against warnings from public health experts.

Highly contagious variants are rapidly spreading in the United States, threatening to outpace the vaccination efforts.

Last week, CDC Director Rochelle Walensky said B.1.1.7, the variant first identified in Britain, is starting to become the predominant strain in many regions of the United States, accounting for 26 percent of COVID-19 cases circulating across the nation.

The country has recorded more than 17,000 infection cases of coronavirus variants as of Tuesday, according to the latest data of the CDC.

Among these cases, 16,275 cases were caused by B.1.1.7. There were 386 cases of a new strain initially discovered in South Africa, called B.1.351, and 356 cases of the P.1 strain first discovered in Brazil.

In addition, the B.1.427 and B.1.429 variants, two coronavirus strains first detected in California, are also being closely monitored by the CDC.

About 168 million COVID-19 vaccine shots have been administered as of Tuesday, while more than 219 million COVID-19 vaccine doses have been distributed across the country, CDC data show.