BRUSSELS, Jan. 2 (Xinhua) -- The European Union (EU) is "closely following" the situation in Iran, the bloc's foreign policy chief Federica Mogherini said in a statement late Tuesday.

The EU top diplomat said the EU "is closely following the ongoing demonstrations in Iran, the increase of violence and the unacceptable loss of human lives."

"We expect all concerned to refrain from violence and the right of expression to be guaranteed, also in light of the statements made by the Iranian Government," she added.

According to unofficial reports, at least 20 people, including civilians and security policemen, were killed and dozens of others injured, as protests against the government's economic and social policies continued in major cities across Iran over the past few days.

Iran's Supreme Leader Ayatollah Ali Khamenei on Tuesday warned of what he calls the enemies' all-out efforts, including inciting unrest, to harm the Islamic republic.

Secretary of Iran's Supreme National Security Council Ali Shamkhani also said certain countries are waging a "proxy war" against the Islamic republic via social media and the internet.

The United States, Britain and Saudi Arabia are behind the recent riots in Iran, he said.

Inflation, unemployment and economic inequality are the major challenges for Rouhani's economic reforms.

According to Iran's Statistical Center, the unemployment rate stood at 12.4 percent during the current fiscal year in Iran.

In August, Rouhani won the second term in office by promising to resolve major economic issues, which he squarely blamed on the decades-long Western sanctions.