NATO member and close U.S. ally Turkey cast doubt Friday on allegations that Iranian agents plotted to kill the Saudi ambassador in Washington, but called on the U.S. and Iran to talk out the issue.
"We don't believe that Iran would be engaged in such an act, but America says they have evidence," Ahmet Davutolgu, Turkey's foreign minister, told a joint news conference with his visiting Iranian counterpart Ali Akbar Salehi.
"Governments should be transparent on such issues. Those who make the claims should also be clear about their claims, and Iran should answer to that," Davutoglu said.
Tehran has denied the allegations, saying they are part of a smear campaign. Salehi said it was a "waste of time" to talk about the accusations.
The affair has aggravated tensions between the United States and Iran. They have had no relations since Iran's 1979 Islamic Revolution and the atmosphere has been poisoned further by Western concerns over Iran's nuclear program.
Davutoglu called on the United States and Iran to address their differences constructively.
"What needs to be done now is that all parties involved share what they have and clear the issue without giving way to a further increase in tensions. Turkey is ready to contribute if there is anything we can do to help relieve the tension."
Turkish media reported this week that the United States had sent representatives to Turkey to present evidence of the alleged plot and discuss the allegations with Turkish officials.
A U.S. embassy spokesman would not comment on the reports. "Our position on this issue is well known," he said.
U.S. President Barack Obama has said Iran will face the harshest possible sanctions for the alleged plot and has not ruled out military action. A U.S. grand jury on Thursday formally indicted two men suspected of being part the plot.
European Union governments agreed on Friday to impose sanctions on five people linked to the alleged plot, after Britain froze the assets of five men, including the two central suspects.
Turkey, which has built up strong trade and political ties over the last years with Iran, has been out of step with the U.S. stance toward Tehran in the past, but it agreed last month to host a radar system for a NATO missile shield programme.
Washington has increased pressure on Ankara to enforce sanctions against Iran over Tehran's nuclear activities.
Turkey says it observes United Nations sanctions against Iran but says it is not obligated to adhere to a separate set of U.S. and European sanctions.
Turkey, Iran against Kurds
During Salehi's visit, Turkey and Iran pledged to to cooperate in the fight against Kurdish militants, as thousands of Turkish troops pressed ahead with an air and ground offensive for a third day following an attack that killed 24 Turkish soldiers.
The counter-insurgency operation against separatist fighters from the Kurdistan Workers' Party (PKK) was concentrated on both sides of Turkey's border with northern Iraq.
Turkey's reaction to one of the most deadly attacks on its security forces in a conflict that began three decades ago has ignited speculation that Turkey could move to a full blown incursion to clear out PKK camps deeper inside northern Iraq.
The prospect would heighten risks in an already unstable region, with U.S. troops due to withdraw from Iraq this year, and neighboring Syria in the grip of a brutal repression against pro-democracy protesters.
Turkey, Iraq, Syria and Iran all have large ethnic Kurdish minorities, but the separatist struggle is fiercest in NATO member Turkey, where more than 40,000 people have been killed in the violence.
At the joint news conference with Davutoglu, the Iranian minister said Kurdish militants were a common problem and the two countries should deepen cooperation against the PKK, and its Iranian offshoot, the Party of Free Life of Kurdistan, or PJAK.
"PKK and PJAK are common problems for Turkey and Iran, our determination continues, we should fight them with more serious coordination," Salehi said.
The Iranian minister described both the PKK and PJAK as "terrorist groups." The United States, European Union and Turkey have listed the PKK as a terrorist organization.
"Our common determination in fighting against PKK and PJAK will continue in the strongest way. We will work together in a common action plan until the area is completely free of the threat of terror," Davutoglu said.