U.S. President Joe Biden on Tuesday announced a new goal to tackle the coronavirus pandemic, saying he will aim to have 70 percent of adults vaccinated with at least one shot and 160 million fully inoculated by July 4, the Independence Day holiday.

He also said the country is shifting to a "new phase" in the mass vaccination campaign, which will focus on younger teenagers waiting to become eligible to receive the shots and adults who have been hesitant to be inoculated due to difficulty in accessing vaccine sites and other reasons.

Noting that the pace of vaccination is slowing as expected, Biden said at the White House, "Soon, we'll have reached the adults who are most eager to get vaccinated and at that point, this effort will shift to a new phase."

U.S. President Joe Biden addresses a joint session of Congress in the House chamber of the U.S. Capitol on April 28, 2021 in Washington (Getty/Kyodo)

Biden has been ramping up vaccination efforts across the country in line with his pledge to get the nation closer to "normal" by July. He had doubled his initial goal to administer 100 million shots in his first 100 days, and the revised target was met.

According to the White House, more than 50 percent of U.S. adults have received at least one vaccine dose. Three vaccines, two of which require a two-dose regimen, have been available in the country for those aged 16 years or older.

The COVID-19 disease has killed more than 578,000 people in the United States, a country with a population of over 300 million, according to data from Johns Hopkins University.

The death toll remains higher than in any other country in the world, but daily deaths have dropped sharply from peak levels.