US Secretary of State Antony Blinken warned on Tuesday that continued Republican opposition to the nomination of ambassadors in the Senate risked undermining American foreign policy.

A handful of Republicans have been blocking the nomination of many envoys in a US Senate heavily divided along partisan lines, particularly by using procedural tricks, leaving key overseas positions vacant.

"Crucial posts, including Beijing, are still vacant. This is a huge problem. And virtually every challenge we face, including dealing with Russia, with China ... are hampered by the fact that we don't have our full national security and foreign policy team on the field," Blinken said.

"For the sake of our national security, the Senate must act."

American ambassadors -- like secretaries and assistant secretaries -- are nominated by the president but can only take up their posts once the upper house of Congress backs the choice in a vote.

US Secretary of State Antony Blinken warned that continued Republican opposition to the nomination of ambassadors risked undermining American foreign policy
US Secretary of State Antony Blinken warned that continued Republican opposition to the nomination of ambassadors risked undermining American foreign policy POOL via AFP / OLIVIER DOULIERY

"In Indonesia, we're very fortunate to have a confirmed ambassador on the job," said Blinken, during a visit to the capital Jakarta.

"But in too many countries, we're still waiting."

Just 16 percent of the current US administration's ambassadors have been confirmed, he said, adding between 70 and 90 percent of envoys had been confirmed at the same point in the previous three American administrations.

Before arriving in Indonesia, Blinken participated in a G7 foreign ministers' meeting in Britain.

As well as the host country and the US, the event was attended by Germany, Canada, France, Italy and Japan, as well as the European Union.

Among these participants, just one has a confirmed US ambassador, an American official told reporters.