U.S. President Barack Obama is set to host an anti-Islamic State (ISIS/ISIL/IS) “countering violent extremism” summit next month in New York, just one year following his vow during a United Nations speech to destroy ISIS.

The coalition partners will take part in the summit on September 29, Agence France-Presse reports, citing diplomats familiar with the upcoming event.

The Islamic State terror outfit has rapidly expanded since Obama’s speech last year, where he promised to “degrade and destroy” the jihadi insurgency. They have continued to gain territory throughout the Middle East and North Africa, in countries such as Libya, Yemen, Afghanistan, Iraq, and Syria.

Since Obama’s speech, ISIS has also secured alliances and pledges of allegiance from prominent jihadi groups such as Boko Haram in Nigeria and Ansar Bayt al-Maqdis (now the Sinai Province) in the Sinai Peninsula.

The President also promised during that speech to stifle the flow of foreign fighters into Syria and Iraq, but since then, that number has grown to at least 22,000 individuals now fighting for ISIS in the Middle East, according to reports.

On Wednesday, the U.S. continued to expand efforts in the anti-ISIS fight, launching manned airstrikes from a Turkish airbase for the first time in the war against the group, the Pentagon announced.

Last month, NATO allies U.S. and Turkey reached an agreement that allows the United States to use Incirlik Air Base to carry out attacks against ISIS. It remains unclear what Turkey received in exchange for allowing U.S. forces to use the airbase. However, the Turkish air force has recently engaged in a heavy bombing campaign against a radical leftist Kurdish separatist group, the PKK.