Iran has delivered its response to an international incentives proposal aimed at persuading the country to suspend a key part of its controversial nuclear program.

There was no indication what the response was, but Iranian state television reports Iran's ambassador to Belgium handed the reply to European Union foreign policy chief Javier Solana in Brussels Friday.  

A spokeswoman for Solana confirmed the EU diplomat had received the response, but she gave no further details. Earlier, the spokeswoman said Solana and Iranian nuclear negotiator Saeed Jalili agreed to remain in contact following what she called "positive and constructive" talks by telephone today.

Solana traveled to Tehran last month on behalf of six world powers (Russia, China, France, Germany, Britain and the United States) to offer economic and trade incentives in return for the suspension of uranium enrichment. The enrichment process can be used to produce nuclear weapons.  

Iranian officials have said they are willing to negotiate details of the incentives package, but refuse to stop enriching uranium.

The United States and its allies accuse Iran of working to develop a nuclear weapon. Iran says its atomic program is for peaceful purposes.

Iran recently offered the world powers its own plan to resolve the nuclear dispute.

In another development, Iran's official news agency says the head of the country's elite Revolutionary Guards has warned that Iran will consider any military action against its nuclear facilities the start of a war.

General Mohammad Ali Jafari is quoted (by IRNA) as saying any country that attacks Iran will regret doing so.

The New York Times newspaper reported last month that Israel conducted a simulated attack on Iran's atomic facilities.

Some information for this report was provided by AFP, AP and Reuters.