Secretary of State Mike Pompeo faced calls Friday to cancel holiday parties due to the raging Covid-19 pandemic, amid fears that the glass-clinking receptions among diplomats will become "superspreader" events.

The State Department has invited hundreds for two customary pre-Christmas parties later this month -- one for foreign ambassadors in Washington and another for the families of US diplomats stationed overseas.

Invitations went out even though Washington's local government has restricted most indoor gatherings to 10 people maximum and despite a soaring pandemic, with the United States reporting a record of more than 210,000 cases on Thursday.

The American Foreign Service Association, the labor union and professional association for US diplomats, called the parties "disconcerting," noting that the State Department has advised US embassies to hold virtual-only receptions this year.

"While attendance at these events is not mandatory for invitees, the same is not true for State Department employees and contract catering workers," it said in a statement.

"The catering workers often do not receive health insurance from their employers and must staff these events in order to keep their jobs," it said.

"We urge the department to reverse course and model responsible behavior in accordance with its own guidelines."

Robert Menendez, the top Democrat on the Senate Foreign Relations Committee, in a letter to Pompeo voiced fear that employees would feel pressure to attend.

"I hope as we approach this difficult and unusual holiday season that you will put the health and wellbeing of department employees and workers first and cancel any in-person events which are clearly not 'mission-critical,'" he wrote.

The State Department said it would check the temperatures of all attendees and require them to wear masks, although most will presumably shed face-coverings to sip drinks.

Hand-sanitizing stations will be set up and all staff will wear gloves at the receptions, which will be split across small rooms at the State Department, White House and nearby Blair House, where foreign dignitaries stay.

"We've taken every precaution to thin out the number of individuals in all spaces at one time, and plan to keep outdoors space open and available to attendees, weather permitting," a State Department spokesperson said.

Pompeo, who is widely seen as having future political aspirations after leaving office next month, has drawn fire in the past for his parties, including taxpayer-funded dinners at the State Department to which he invited prominent Republicans.

President Donald Trump and a number of other people tested positive for Covid-19 after a White House event on September 26 in which he nominated a conservative justice to the Supreme Court, Amy Coney Barrett.