"ISIS [Daesh] has used chemical weapons on the battlefield in Syria and Iraq… are seeking to develop chemical weapons as well," Nielsen said. "It is only a matter of time before they try to organize these methods into Western attacks."
Nielsen underlined that the Trump administration was going to intensify the vetting of all refugees admitted to the United States from countries with serious terrorist problems.
"I am announcing security upgrades to the… refugees program," she said. "We will be rolling out new security measures for applicants from high risk countries. These changes will help us better assess legitimate refugees."
The official explained that the US government had to do more to keep dangerous individuals out of the United States in the first place.
Accusations Against Russia, Syria and Paris Meeting
Despite the US accusations against Russia of alleged covering up chemical weapons use in Syria, Nielsen's stance repeats the concerns voiced by the Russian Foreign Minister Sergei Lavrov on January 18, during a UN Security Council meeting on non-proliferation of nuclear weapons.
Lavrov pointed to a growing threat of 'chemical' terrorism in the Middle East, referring to Iraq and Syria and blaming some countries for turning a blind eye to the growing threat.
Nielsen's statement comes in wake of January 23 Paris meeting of the so-called International Partnership Against Impunity for the Use of Chemical Weapons. Russia and China did not take participate among 24 countries, as they weren't invited. The attendees of the meeting accused Damascus of being responsible for chemical attacks in Syria and Moscow of trying to cover up the alleged crimes of Syrian government troops. Russia has repeatedly refuted the allegations, saying that such accusations are aimed at discrediting the Syrian government.
Supporting this position, the Russian Defense Ministry specified that Washington had ignored the fact that terrorists have been using chemical warfare agents against Syrian government forces and civilians.