Gen. Yousef Huneiti denied reports that HRH Prince Hamzeh had been arrested but said the prince was asked to "cease all activities or movements exploited to target Jordan's security and stability" as part of comprehensive investigations conducted by security authorities.
Arrests of top officials close to royal family members are rare in Jordan.
The United States, which considers Jordan a critical ally and has partnered with the country for years on USA -led counterterrorism operations, said that Abdullah had its "full support".
Emirati official Anwar Gargash said on Twitter that Jordan's stability was a priority for the region, and that the country's "wise policy of building bridges in a turbulent region was not an easy choice but was, and remains, the necessary direction".
Prince Hamza, who had been groomed by his mother Queen Noor to succeed his late father King Hussein, has been pushed into the political wilderness since he was sacked as crown prince.
Tribes who dominate the security forces form the bedrock of support for the kingdom's Hashemite monarchy.
Abdullah succeeded his father King Hussein, who ruled Jordan for almost five decades.
Which countries backed the king?
Since the news broke Saturday, #Prince_Hamzeh has trended on Twitter, along with messages of solidarity with the prince from followers in Jordan and overseas.
Jordan has always been a key Western ally and an island of stability in a turbulent region.
In a statement, GCC Secretary General Nayef Falah Mubarak al Hajraf said the bloc affirmed its full support for all decisions and measures taken by King Abdullah to preserve the security and stability of Jordan. "All the solidarity with the Jordanian leadership and King Abdullah in defending the gains of the Jordanian people, protecting their stability, and refusing interference in their affairs".
Safadi added that the investigation revealed that phone calls made by some of the accused discussed the most appropriate time to start steps to destabilize the security of Jordan. "King Abdullah is a key partner of the United States, and he has our full support", he said.
Safadi said Awadallah was in contact with the so-called "foreign opposition", which aimed to incite the people against the Jordanian state. The individual offered his services at her disposal while offering her a plane immediately to get out of Jordan, Safadi said.
"Ahmed Aboul Gheit added that King Abdullah II has a high and appreciated position, whether among the Jordanian people or on the Arab level in general, and that everyone knows his sincerity and his great role in serving Arab causes". He commands a loyal following in Amman and, with his trim mustache and checkered keffiyeh headdress, often styles himself after his father, the late King Hussein, a revered figure in Jordan.
But he did not think there is a credible threat to Abdullah's rule and it is unlikely to lead to a popular uprising.
Safadi said the King chose to talk directly with Prince Hamzah to deal with the issue within the family, and to discourage him for these activities, "that target and exploit the security of Jordan and Jordanians and constitute a departure from the traditions and values of the Hashemite family".
Abdullah had appointed Hamzah crown prince in 1999 in line with Hussein's dying wish, but in 2004 stripped him of the title and gave it to his own eldest son Hussein.
Before becoming royal court chief in 2007, he was head of the king's cabinet in 2006.
Hamzah's videotaped statement came after two former senior officials and other suspects reportedly had been arrested for "security reasons", even as authorities denied that Hamzah had been detained or placed under house arrest.
It declared independence in 1946, and despite having little oil wealth, severely lacking water and repeatedly being rocked by wars on its borders, the kingdom has managed to survive the regional upheavals.