International efforts to break the nuclear deadlock with Iran continue to be very difficult, European Union chief diplomat Javier Solana said Monday, according to DPA. Solana, who met Iranian nuclear negotiator Ali Larijani in Ankara late last month, said he was determined to keep open channels of communication with Tehran. However, "the situation is very difficult," Solana told the European Parliament. Iran continued to resist UN calls for a suspension of uranium enrichment before the start of any formal nuclear talks, said Solana. "For the moment this is very difficult to obtain," the EU chief diplomat said. He added, however, that another meeting with Larijani was planned in the next few weeks. Solana has been mandated by the five permanent members of the United Nations Security Council - the US, Britain, France, Russia and China - as well as Germany to persuade Iran to open formal nuclear negotiations in exchange for western trade and aid concessions. These would include access to civilian nuclear technology. The EU foreign and security policy chief said that negotiations with Iran - once they started - would not be open-ended and last for about six months.