"A country's presence on the foregoing list is not necessarily a reflection of its government's counternarcotics efforts or level of cooperation with the United States," Trump said.
The reasons countries are placed on the list is the combination of geographic, commercial, and economic factors that allow drugs to transit or be produced, even if a government has engaged in robust and diligent narcotics control measures, he said.
Simultaneously, Trump designated Bolivia and Venezuela as countries that have failed demonstrably during the previous 12 months to adhere to their obligations under international counter-narcotics agreements.
He also determined that support for programs to aid the promotion of democracy in Venezuela are vital to the national interests of the United States.
Asserting that combatting the ongoing United States opioid epidemic is one of his Administration's most urgent priorities, Trump said his government has dedicated nearly $4 billion in additional funding to confront this national crisis.
The Trump Administration is committed to addressing all factors fueling the drug crisis, which is devastating communities across America, including steps to curb over-prescription, expand access to treatment and recovery programs, improve public education programs to prevent illicit drug use before it begins, and to strengthening domestic drug enforcement at the borders, he said.
"Alongside these massive and historic United States efforts, I expect the governments of countries where illicit drugs originate and through which they transit to similarly strengthen their commitments to reduce dangerous drug production and trafficking, Trump said.
In his presidential determination, Trump expressed his deep concerns that illicit drug crops have expanded over successive years in Colombia, Mexico, and Afghanistan, and are now at record levels.
Drug production and trafficking in these three countries directly affect the US national interests and the health and safety of American citizens, he said.
"Heroin originating from Mexico and cocaine from Colombia are claiming thousands of lives annually in the United States. Afghanistan's illicit opium economy promotes corruption, funds the Taliban, and undermines that country's security, which thousands of United States servicemen and women help defend," Trump said.
Despite the efforts of law enforcement and security forces, these countries are falling behind in the fight to eradicate illicit crops and reduce drug production and trafficking, he rued.
As such, Trump said that these governments must redouble their efforts to rise to the challenge posed by the criminal organisations producing and trafficking these drugs, and achieve greater progress over the coming year in stopping and reversing illicit drug production and trafficking.
The US will continue its strong support for international efforts against drug production and trafficking, as well as to strengthen prevention and treatment efforts in the United States, he added.