BAGHDAD, Jan. 13-- The current strategy of the United States and its allies in the fight against the Islamic State (IS) is unlikely to succeed and more international coordination is needed, said experts.

In the past few months, the IS has not only repeatedly hit press headlines with online execution videos, it has also captured large swaths of land in Iraq and Syria.

The militant group now controls some 300,000 square km of land and its number of fighters surged to above 100,000, posing severe threats to regional security.

Ibrahim al-Ameri, a professor of politics at Baghdad University, said that compared with al-Qaida, the IS has a more complicated and advanced structure, testified by the fact that the group has not slowed its military advances in Iraq and Syria despite reports about the death of its supreme leader Abu Bakr al-Baghdadi. The U.S.-led air raids seemed to have made little impact in weakening the IS, he said.

Moreover, the IS appears to be a better publicist in advocating its ideas. The online videos by the IS with English subtitles are of much higher quality than al-Qaida's home-video style propaganda.

"With these means, the IS could in the name of religion lure more young people from Western countries to take part in the so-called Holy War in the Middle East," al-Ameri said.

The IS militants are running rampant for another reason: the group has an appalling resilience in withstanding strikes from outside, another expert said.

Persistent airstrikes by the United States and its partners targeting the extremist group have indeed weakened its communication networks, dented its combat capability and made it impossible for the group to assemble large troops, said Najib al-Jubouri, a political commentator in Iraq.

However, as the scope of air raids expands, IS militants started to hide among civilians, making the airstrikes less effective, al-Jubouri said, noting that the allies could hardly uproot threats from the IS simply via airstrikes.

Considering the new trend of terrorism in recent years, the international community should take measures to enhance cooperation and coordination in security and counter-terrorism, he said.

Specific moves should include more efforts in collecting and sharing anti-terror information, the enhancement of counter-terror efforts in cyberspace and the severance of financial channels of the IS, the commentator said.

Al-Jubouri also suggested the allies consider the option of providing economic support to the Iraqi government to finance its war with the IS, as the country's budget deficit widens with dwindling oil revenue.

Wwhile the security situation in Iraq, Syria and neighboring countries continues to deteriorate, there is also an apparent increase in terror threats against Western countries, and the Boko Haram and al-Shabaab have become a scourge in Africa, said al-Ameri.

"Year 2015 is a key year in anti-terrorism endeavor and members of the international community should wait no more to join hands to combat terrorism," he said.