TEHRAN - Iran's supreme leader Ayatollah Ali Khamenei accused Washington of failing to respect the terms of a nuclear deal that lifts sanctions on Tehran, in a speech Sunday marking Persian New Year.

"The Americans have not respected their commitments," he said in the speech for Nowruz in the northeastern city of Mashhad.

The United States has lifted sanctions "on paper" under Tehran's nuclear deal with world powers that came into effect in January, "but they are using roundabout paths to prevent the Islamic republic from achieving its targets", Khamenei said. "They have said they lifted the sanctions... but, in fact, they are working to prevent the lifting of sanctions from taking effect," he said.

The Nowruz holiday comes just two months after implementation of the deal began, triggering the lifting of a raft of international sanctions and raising the prospect of renewed foreign investment. But Khamenei said the Western allies of Washington remained "afraid" of dealings with Iran.

"Today, in all the Western countries which are under their influence, banking transactions come up against problems," he said. "When we investigated, we realised that they are afraid of the Americans." In a pre-recorded television address broadcast earlier on Sunday, he said: "The economy must be our priority."

The end of the 13-year standoff over Iran's nuclear programme has raised expectations of recovery after years of economic difficulty, including high inflation which dramatically reduced Iranians' purchasing power. The economy exited a deep recession little more than a year ago.

But although international oil sales have resumed and exports risen since January, the price of crude means receipts have been low and growth remains weak. "The solution is the economy of resistance," Khamenei said. "With the economy of resistance, we can fight unemployment and recession, control inflation and confront the threats of enemies."

He said President Hassan Rouhani's government had put in place "extensive measures" to repair the economy. "Steps have been taken and these preliminary actions must continue," the supreme leader said, in a possible nod to Rouhani's taming of inflation, which has fallen to 13 percent from more than 40 percent when the president took office in August 2013.

"I do not expect that these problems will be solved in a year, but I'm sure that if appropriate actions are taken, we will see the effects at the end of the year." Unemployment in Iran stands at a little over 10 percent but youth unemployment is around 25 percent, making job creation vital. In a separate message, broadcast immediately after Khamenei's, Rouhani echoed the supreme leader, and said economic growth of five percent was his aim for the next 12 months. "I have hope, and am certain that with interaction with the world, we can move towards economic prosperity," he said.

Throughout the 12-year standoff that preceded the agreement, Iran always denied wanting nuclear weapons, saying its nuclear activities were exclusively for peaceful purposes such as power generation.

"The nuclear deal was never intended to resolve all the disputes between our two nations, and the United States continues to have profound differences with the Iranian government," Obama said.

"But even as our two governments continue to have serious disagreements, the fact that we are now talking to each other on a regular basis, for the first time in decades, gives us an opportunity, a window, to resolve other issues." "As we do, I firmly believe we can continue to expand the connections between the American and Iranian people," Obama added.

Washington cut diplomatic ties with Iran in 1979, when its embassy in Tehran was stormed by students, months after the Islamic revolution, leading to a 444-day hostage crisis.

Obama will help bury the hatchet in a separate diplomatic dispute on Sunday when he arrives in Cuba after a more than half-century-long Cold War conflict that turned the communist island and its giant neighbor into bitter enemies.

"My visit will be a reminder that even after decades of mistrust it is possible for old adversaries to start down a new path," Obama said.

"As you and your families welcome the new spring this Nowruz, I wish you a happy, healthy and prosperous new year, and I hope that the friendship and ties between the American and Iranian people will continue to grow," he added.

Iran's supreme leader said Sunday that the economy must come first, insisting in a Persian new year's day message that domestic production is the best route to a strong recovery.

The Nowruz holiday comes just two months after implementation began of a landmark nuclear deal between Iran and world powers led by the United States, triggering the lifting of a raft of international sanctions and raising the prospect of renewed foreign investment.

Ayatollah Ali Khamenei has said repeatedly that foreign investment will only help if it is used to develop Iran's domestic industries.

"Hopes exist for the year 1395... but to achieve these hopes we must make efforts day and night without interruption," Khamenei said in a pre-recorded television address. "The economy must be our priority," he said, dubbing 1395 "the year of the resistance economy and action".

The ending of the 13-year standoff over Iran's nuclear programme has raised expectations of recovery after years of economic difficulties, including high inflation which dramatically reduced Iranians' purchasing power. The economy exited a deep recession little more than a year ago.

But although international oil sales have resumed and exports risen since the nuclear deal went into effect in January, the price of crude means receipts have been low, and growth remains weak.

"The solution is the economy of resistance," Khamenei said. "With the economy of resistance, we can fight unemployment and recession, control inflation and confront the threats of enemies."

He said the government of President Hassan Rouhani had put in place "extensive measures" to repair the economy.

"Steps have been taken and these preliminary actions must continue," the supreme leader said, in a possible nod to Rouhani's taming of inflation, which has fallen to 13 percent from more than 40 percent when the president took office in August 2013.

"I do not expect that these problems will be solved in a year, but I'm sure that if appropriate actions are taken, we will see the effects at the end of the year."

Unemployment in Iran stands at a little over 10 percent but youth unemployment is around 25 percent, making job creation vital.

In a separate message, broadcast immediately after Khamenei's, Rouhani echoed the supreme leader, and said economic growth of five percent was his aim for the next 12 months.

"I have hope, and am certain that with interaction with the world, we can move towards economic prosperity," he said.