"By decree, we intend to guarantee the POSSESSION of firearms for the citizen without criminal antecedents, as well as make its registration definitive," Bolsonaro wrote on Twitter.
The loosening of firearms laws was one of the key platforms in Bolosonaro's campaign for the 2018 elections. The former army captain will take office on January 1.
Bolsonaro gave no further details and it was not immediately clear what mechanisms he will have at his disposal to carry out such a decree, or what specific measures the decree would contain.
Brazil's Congress is already discussing measures to loosen gun laws.
The Workers Party's (PT) leader in the Lower Chamber, lawmaker Paulo Pimenta, criticized the decision, describing it as "payment to the lobby of the arms industry in Brazil, the United States and Israel."
Pimenta placed responsibility for any innocent person that might be killed by firearms in the hands of people without training or psychological assessment firmly on Bolsonaro and former Judge Sergio Moro.
Posting on Twitter, Pimenta continued: "1. Any manager and a minimally informed person knows that more guns in the society are a stimulus to violence and are far from being any solution to public safety; 2. The deaths of innocents by the hands of armed people without any training and psychological assessment, tragedies in family quarrels and discussions with neighbors or in transit will be in the account of Jair Bolsonaro and Sérgio Moro; 3. The decision of Bolsonaro and Moro is payment to the lobby of the arms industry in Brazil, the US and Israel. The companies of these two countries, notorious for spending more on warfare than public health and education, will have a huge market in Brazil to increase their profits."
Possession of firearms in Brazil is currently restricted. Civilians need to go through a long process of verification and only small-caliber guns are sold.
According to federal law, Brazilian must be over 25, have a legally recognized job, a specific residency, not have any criminal processes open, prove their technical and psychological capacities and declare their need for a gun.
Even with the laws that regulate guns in Brazil, according to a study published in August by the Global Burden Disease, the South American country in 2016 had the highest number of deaths by firearms: 43,200.
According to the authors of the report, "Ninety per cent of violent deaths occur outside conflict situations. Around the world, firearms are often the lethal medium in cases of homicide, suicide and unintentional injuries, indicating a major public health problem with social and economic costs that extend beyond the immediate loss of life."