The British embassy in the Jordanian capital, Amman, has been closed until further notice due to security fears.
In November, suicide bombers killed 60 people in Amman
Plans for attacks against western visitors to the country are thought to be in the "final stages", according to the Foreign Office.
It has revised its travel advice, saying "sensible precautions" should be taken when visiting Jordan.
In November, three suicide bombers killed 60 people and injured nearly 100 in hotels in Amman.
The Foreign Office travel advice summary reads: "Terrorists may be in the final stages of planning attacks against Westerners and places frequented by Westerners.
"The British Embassy in Amman will be closed until further notice due to the security situation."
It goes on: "There have been a number of successful and attempted terrorist attacks in Jordan since 2001."
Extra care should be taken "when using Jordanian service taxis to cross into neighbouring countries" and, in particular, "at the borders with Israel and Iraq".
Visitors are advised to regularly check the Foreign Office website for updated guidance and to arrange comprehensive travel and medical insurance before travelling.