US officials have called the charges groundless and demanded that Brunson, who remains under house arrest, be allowed to return to the United States.
Following unsuccessful negotiations last week to resolve Brunson's case, President Donald Trump announced at the weekend that he was imposing new tariffs on Turkish steel and aluminum, sending the lira into free-fall.
Today, in an apparent reference to the US, Erdogan told a gathering of foreign ambassadors that "the bullies of the global system cannot roughly, shamelessly encroach on our gains that were paid for by blood," according to the Hurriyet Daily News.
"We will overturn the scenarios that target our nation," he added.
Erdogan has remained defiant throughout the crisis, portraying the lira's slide as the consequence of economic sabotage against Turkey, while urging his citizens to sell dollars and gold to support the local currency.
Turkey's Interior Ministry said that it was taking legal action against more than 300 social media accounts that had posted messages that harmed the lira, local media reported.