US president Joe Biden said on Tuesday he has made up his mind on how to respond to a drone attack that killed US service members in Jordan, as he weighs punishing Iran-backed militias without triggering a wider war.

Mr Biden, speaking to reporters as he left the White House on a campaign trip to Florida, did not elaborate on his decision, which came after consultations with top advisers at the White House.

He said the United States does not need a wider war in the Middle East, echoing comments from other officials on Tuesday that the United States does not want a war with Iran.

Mr Biden has been weighing his options and the expectation has been that there will be retaliatory strikes, but the timing of the response has been unclear.

Three US service members were killed and at least 34 wounded in a drone attack by Iran-backed militants on US troops in northeastern Jordan near the Syrian border, officials said on Sunday.