Days after the U.S. and UK suspended the operations of its global network of embassies and consulates, U.S. intelligence officials disclosed the terrorist group Al Qaeda may have already developed a liquid explosive highly undetectable even by the most sophisticated scanning machines.

The new "ingenious" substance, as it is currently called, was believed to have been developed by Ibrahim al-Asiri, al-Qaeda's bomb maker in Yemen, according to two unnamed senior U.S. intelligence officials. Al-Asiri is the brains behind the bombs constructed for the "underwear bomber" plot of 2009.

To turn the substance into a bomb, one only needs to dip articles of clothing into the liquid and let it dry. Once dry, they become highly explosive.

"It's ingenious," one official told ABC News. The latter confirmed that all the current technology employed by the Transportation Security Administration proves useless and would not be able to detect the explosive.

Yoram Schweitzer, an Israeli terror expert from the Institute for National Security Studies, said it was highly possible the al-Qaeda could be developing such technology since it needs to create a device that could evade security restrictions.

"One of the characteristics of the organization is its continuous efforts to innovate new means of overcoming defenses against them," Mr Schweitzer told The Times of Israel. "I can promise you that professionals are doing everything in their power to cope with this threat."

"The current safeguards, such as the liquids ban or the more traditional magnetometer and x-ray scans, cannot detect this new explosive to prevent someone from smuggling a bomb onto a passenger plane," Scott Kleinmann, a research fellow at the London-based International Centre for the Study of Radicalisation and Political Violence and a terrorism expert, told The Times of Israel.

Mr Kleinmann highly believed Al-Asiri will indeed use the new explosive to the test. "He continues to improve the concealment of suicide bombs with creative designs."

"AQAP (al-Qaeda in the Arabian Peninsula) has also shown their propensity to carry out bomb attacks. Almost every year since 2008, they have planned or carried out a major bomb attack against the U.S.," Mr Kleinmann added.

In 2008, al-Qaeda bombed the U.S. Embassy; a U.S. airliner in 2009; and a U.S. cargo plane in 2010. In 2012, it was another underwear bomb. And for 2013, the plot has been targeted against embassies.

Earlier this week, the U.S. State Department suspended the operations of its diplomatic posts. It likewise issued for U.S. citizens a worldwide travel alert over fears of a planned terror attack. On Tuesday, the department ordered all its non-essential staff at its Yemen embassy to leave the country.

Read: Al-Qaeda Threat: US, UK Closes Global Embassies, Consulates Following Intercepted Terrorist Attack Message, Eyes on Yemen