Jordan has declared its border regions with Syria and Iraq to be closed military zones after a suicide bombing on Tuesday that killed six soldiers.
It is not clear who was behind the attack, which was launched from Syrian territory, close to a refugee camp.
The Jordanian government said no new refugee camps would be built and none would be expanded.
Dozens of people have taken part in a candlelit vigil in the capital, Amman, in memory of the victims.
Tuesday's attack, the first of its kind since the conflict in Syria began in 2011, saw a lorry full of explosives driven at high speed over the border from Syria and blown up beside a Jordanian military post.
Jordan is part of the US-led coalition fighting so-called Islamic State in Syria and Iraq.
"Any vehicle and personnel movement within these areas that move without prior co-ordination will be treated as enemy targets and dealt with firmly and without leniency," an army statement said.
The order went into effect immediately.
Jordan's Information Minister, Mohammed Momani, told the BBC there had been warnings for months that militants, including IS members, were hiding among Syrians stuck at the borders.
He said Jordanians were angry at the attempt to undermine their country's security and stability.
International relief workers warned that Jordan's suspension of all humanitarian aid to the area could put the lives of refugees at risk.
Rukban is the last crossing where refugees fleeing violence in Syria and Iraq can gain entry to Jordan.
Tens of thousands are currently stranded in this remote area of the desert, and depend on daily deliveries from the Jordanian side to survive.
Mr Momani said humanitarian cases would be assessed by the armed forces at the crossing.
Jordan is one of the biggest hosts of Syrians displaced by conflict, currently home to more than 600,000 refugees registered with the UN.