Hours before the government was set to shutdown, congressional leaders announced they came to an agreement over a $900 billion COVID-19 relief bill.

A final vote on the spending bill and COVID-19 relief bill will be on Monday in the House, before it heads to the Senate.

Lawmakers agreed to a $300 boost in weekly unemployment benefits, $600 relief checks for individuals, more than $300 billion for small business aid and huge pots of money for schools, hospitals and vaccine distribution.

-ABC News' Mariam Khan and Allison Pecorin contributed to this report.

Four more countries announced they will suspend flights from the United Kingdom after a new strain of the coronavirus was discovered in the country.

Saudi Arabia's Ministry of Interior announced it would suspend all international flights, except in "exceptional cases" for at least one week.

Turkish Health Minister Dr. Fahrettin Koca tweeted his country would temporarily ban all fights from U.K., Denmark, Netherlands and South Africa.

In Switzerland, the Swiss Civil Aviation Authority announced flights from the U.K. and South Africa would be suspended starting at midnight "until further notice."

Latvian Prime Minister Arturs Krišjānis Kariņš tweeted that flights to and from the U.K. would be suspended from midnight to at least Jan. 1

-ABC News' Dragana Jovanovic and Aicha El Hammar Castano contributed to this report

The Centers for Disease Control and Prevention's advisory committee voted 13-1 on who would receive the vaccine in groups "1b and 1c" and who would be "essential."

Phase 1b includes people over 75 and front-line essential workers, while phase 1c includes younger patients with high-risk medical conditions and other essential workers.

Those two groups would cover K-12 teachers, school staff, child care workers and critical workers in high-risk settings.

It would also include people in homeless shelters, prisons, jails, detention centers and mental development centers and staff who work in these places, according to the CDC.

The committee also defined front-line essential workers as first responders, educators, food and agriculture workers, manufacturing workers, corrections workers, U.S. postal workers, public transit workers and grocery store workers.

The front-line essential workers represent about 30 million Americans, according to the CDC.

The CDC is expected to sign off on these recommendations to make the next phase of vaccines available to Americans over 75 and front-line workers, but it will ultimately be up to states to define which front-line workers qualify.

-ABC News' Adisa Hargett-Robinson and Stephanie Ebbs contributed to this report

Half a million Americans received Pfizer vaccine in first week: CDC

The Centers for Disease Control released its first set of data on the Pfizer coronavirus roll out.

As of Sunday afternoon, at least 556,208 doses have been administered and 2.8 million doses have been distributed throughout the country, according to the CDC.

The first doses were given out to hospital workers, nursing home staff and federal elected officials starting on Dec. 14. Those patients will need a second dose in a few weeks.

The CDC told ABC News it plans to transition this data to agency's COVID Data Tracker in the next couple weeks and have data available down to the jurisdictional level.

A coronavirus vaccine manufactured by Moderna began shipping on Sunday and is slated to be administered this week.

-ABC News' Eric Strauss contributed to this report.