Washington has imposed sanctions on Venezuelan officials it accuses of corruption, and on certain financial transactions with the Maduro government, which it accuses of violating human rights and triggering an economic meltdown. Ties between Turkey and the United States, two NATO allies, have also been strained.
US President Donald Trump last month signed an executive order banning anyone in the United States from dealing with entities and people involved in "corrupt or deceptive" gold sales from the South American country.
Turkey this year has become the largest importer of non-monetary gold from Venezuela, Reuters reported.
"Political problems cannot be resolved by punishing an entire nation," Erdogan said, with Maduro by his side at a forum attended by business people from both countries. "We do not approve of these measures that ignore the rules of global trade."
Venezuela is suffering a bout of hyperinflation and a fifth year of recession that has led to shortages of food and medicine. Maduro frequently blames a US "economic war" for the country's woes, but critics say the crisis is proof socialist policies started under his predecessor Hugo Chavez have failed.
While Erdogan did not directly mention the United States or Trump, he said his "friend" Maduro was facing "manipulative attacks from certain countries and acts of sabotage from economic assassins." In response, Erdogan said he was willing to strengthen trade ties.
Trade between the two countries have been growing, with Turkish data showing the country imported $900 million in gold from Venezuela in the first nine months of the year. Without naming the United States, Maduro decried sanctions and said Venezuela had the right to sell gold.
"It is very petty to try to use an illegal sanction to prevent Venezuela from selling its gold to the world," Maduro said during a joint press conference later on Monday with Erdogan, who also visited Paraguay after attending the Group of 20 summit in Argentina last weekend.
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