WASHINGTON: President Donald Trump on Friday condemned the arrest of protesters in Iran, telling Tehran that “the world is watching” as officials reported fresh demonstrations over the country’s struggling economy.

Fifty-two people were arrested in Iran’s second city Mashhad on Thursday, the first day of the protests, which also took place in other areas and spread to the capital Tehran as well as Kermanshah the following day.

“Many reports of peaceful protests by Iranian citizens fed up with regime’s corruption & its squandering of the nation’s wealth to fund terrorism abroad,” Trump tweeted.

“Iranian govt should respect their people’s rights, including right to express themselves. The world is watching! #IranProtests.”

Trump has repeatedly taken aim at Iran, denouncing its government as a “fanatical regime” and accusing it of violating an international agreement aimed at curbing Tehran’s nuclear programme, refusing to certify its compliance with the deal.

State Department spokeswoman Heather Nauert also addressed the protests.

“The United States strongly condemns the arrest of peaceful protesters. We urge all nations to publicly support the Iranian people and their demands for basic rights and an end to corruption,” she said in a statement.

Iranian First Vice-President Eshaq Jahangiri suggested hardline opponents of the government may be behind the demonstrations, which reportedly remained small on Friday.

“Some incidents in the country these days are on the pretext of economic problems, but it seems there is something else behind them,” Jahangiri said in comments carried by state broadcaster IRIB.

“They think by doing this, they harm the government,” he said, but “it will be others who ride the wave”.