Syrian President Bashar Al Assad has openly threatened Jordan. He accused it of allowing hundreds of armed rebels it has allegedly trained to enter Syria.
Perhaps the more alarming thing Assad said was that the fire will not stop at Syria's borders because "the entire world knows Jordan is just as exposed to the crisis as Syria."
This is a direct threat to Jordan and the West.
Though Jordanian officials have been reluctant to respond to Assad's statements, some say Jordan is used to warnings from him.
Assad and King Abdullah II have had their fair share of differences ever since they both came to power around the same time 13 years ago.
Relations between Jordan and Syria have historically been tense well before the conflict began in Syria. But to this day, the two countries have not cut their diplomatic ties.
Since the outbreak of violence in the southern Syrian Daraa province bordering Jordan in March 2011, Assad has accused his southern neighbour of stirring trouble in his country. The truth is the spark that lit the Syrian uprising started after 15 school children wrote anti-government graffiti on a wall in Daraa, demanding the downfall of Assad's regime. They were thrown in jail. And that's when Syria got its first strong taste of rebellion in the Arab Spring.
It wasn't the Jordanians who told these children what to write on Daraa's walls. But Assad has always found a way to blame Jordan for the turmoil in southern Syria and brush aside the fact that he faces real opposition to his rule.
Whether they admit it or not, Jordanian officials are relatively shaken by Assad's statements.
There is no doubt that the Pentagon's decision to send a contingent of US troops to Jordan raises the question of whether the Obama administration has now moved one step closer to a possible military intervention in Syria.
Since last year, there have been numerous rumours about the presence of foreign boots on the ground in Jordan. Now their presence, as well as plans to send more troops to boost Jordan's defence capabilities, has been confirmed by both US and Jordanian officials.
The latter say they maintain their official position rejecting military intervention in Syria. And the US says its team of army planners in Jordan aims to strengthen the army's capabilities in dealing with the threat of Syrian chemical weapons, should they be smuggled into the country.
But Assad may have directed his warnings at Jordan because he's starting to feel uncertain and insecure about the most strategically important Syrian border: the one it shares with Jordan. Though the Syrian army has lost some of its official border crossings with Iraq and Turkey to rebel control, until now the Syrian army is adamant about manning the two it shares with Jordan: Daraa-Ramtha and Nassib-Jaber.
Should control of these border crossings and consequently Daraa province fall in the hands of rebels, then Assad should expect rebels to make quick and big advances in Damascus. Daraa and Damascus are separated by an unfussy 90-kilometre highway. Maintaining control of the border with Jordan prevents a heavy rebel offensive via that highway in the city of Assad's seat of power. This is why tight control of Syria's southern border is imperative for Assad's survival.
Jordanian officials and analysts say 200 US troops in Jordan won't change much. Depending on who you ask their deployment may or may not pave the way for foreign military intervention in Syria.
Though Assad has explicitly threatened Jordan, observers say there is little he can do at this point in terms of launching an attack on the kingdom. He's struggling for territory control inside Syria. Attacking neighbours would be a waste of his military resources and could invite foreign military intervention sooner.
The more worrying measure Assad could resort to is activating his loyal sleeper cells inside Jordan to launch an attack on Jordanian soil. This is why Jordan needs to beef up security at its border and inside the country. And that it seems to be already doing.