TEHRAN -- Iran's Supreme Leader Ayatollah Ali Khamenei said Tuesday that the next Iranian president should focus on the country's economy which is targeted by the West.

Khamenei's remarks came as some presidential candidates in their campaign put "improving of the relations" with the world, including Western countries, as a prerequisite to solve Iran's nuclear issue and economic problems.

The candidates "should pledge to deal with the subject of economy which is at the top of Western hostility with Iran," said Khamenei when addressing a large crowd of people and local authorities who gathered to commemorate the death anniversary of founder of the Islamic republic Ayatollah Ruhollah Khomeini.

"Some (of the candidates) said... that we (should) make concessions to the enemies to appease them; but we should know that they are worried about... a powerful and resistant Islamic republic," said the Iranian leader, implying that Iran's "dignity and power" is attainable through resistance to mounting Western pressure over the country's nuclear program.

On Monday, the U.S. administration expanded sanctions against Iran to target the Islamic republic's currency for the first time as well as its auto industry.

U.S. President Barack Obama approved a new executive order allowing tightening sanctions on Iran in his administration's continuous efforts to force the country to stop its uranium enrichment activities.

Under the order, foreign financial institutions will be hit with sanctions for making "significant" transactions in the purchase or sale of the Iranian rial, or for maintaining " significant" accounts outside Iran denominated in the Iranian currency, which has reportedly lost half of its value since the beginning of 2012 as a result of U.S. sanctions.

Sales of goods or services for the manufacturing or assembling in Iran of light and heavy vehicles, including passenger cars, trucks, buses, minibuses, pick-up trucks and motorcycles, are subject to sanctions as well.

Iran insists on the peaceful nature of its nuclear program, while the West regards it as a cover for making nuclear weapons.

On Tuesday, Khamenei said that the enemies of Iran want to use the Islamic republic's upcoming presidential election to cause " sedition" in the country.

They are also trying to "discourage" people from taking part in the vote by resorting to numerous "plots," said Khamenei, adding that the Iranian people will "give decisive response to the enemy' s plots" by a massive turn-out in the election.

On Sunday, the Iranian intelligence ministry announced that it had busted a terrorist cell plotting to carry out sabotage activities in the presidential election slated for June 14.

The head of the cell once worked for an undisclosed Arab country and later contacted Israel's Mossad, the ministry said in a statement, adding that the terrorist formed a 12-member team to conduct sabotage and terrorist activities in Iran.

The Iranian supreme leader added that Iran's forthcoming election is an opportunity for the Islamic republic and a high turn-out of voters will testify to the people's confidence in the Islamic establishment.

According to Iran's interior ministry, nearly 50.5 million eligible voters will cast ballots in the election contended by eight candidates, most of whom are conservatives.