Ilham Aliyev and the offending flag, as seen on Azeri TV
A row over flags is threatening to sour relations between Azerbaijan and Iran, following a visit by the Azeri leader to Tehran last week.
In pictures shown on Azeri TV, the Azeri flag displayed on a table during a meeting between Azerbaijani President Ilham Aliyev and Iranian Expediency Council head Akbar Hashemi Rafsanjani appeared to be the wrong way up.
The Azeri tricolour is supposed to be displayed with the blue stripe at the top, but the flag seen on the TV has the blue stripe at the bottom and the central crescent moon back-to-front.
A leading Azeri opposition daily, Azadliq, is now spearheading a campaign to try to shame Iran into apologising for having slighted an Azerbaijani state symbol.'Mistake'
The paper has run a commentary under the heading "Iran, apologise to Azerbaijan" several times and called on other media to follow suit.
The Azeri flag the right way up
The blue stripe symbolises Turkic peoples
The red stripe stands for modernity
Green is the colour of Islam
"We urge all patriotic colleagues to teach Iranian politicians a lesson because they show disrespect for the Azerbaijani state and its symbols," it said.
And to make the point even more forcefully it is publishing Iran's green, white and red flag upside down in its own pages.
Azadliq editor-in-chief Qanimat Zahid told the BBC that the paper expects the Iranian embassy in Baku to say it is sorry or publicly explain how the incident occurred.
But the embassy sees no reason to apologise.
"There were more than 50 flags of Azerbaijan during the president's visit and only one flag was wrong," Iranian Ambassador to Azerbaijan Afshar Soleymani told AFP.
"I don't see the problem. This is a mistake."Protest
Azerbaijan and Iran have a long history of close ties, but in recent years relations have been strained over a number of issues, including the legal status of the Caspian Sea.
Two other Azeri opposition newspapers have joined Azadliq's campaign, but not all readers are happy with it.
In addition to a protest from the Iranian embassy, some locals have contacted the paper with "mild reproaches".
"Since we started our campaign several readers have called at our editorial offices, saying that they welcome our demand that Tehran apologise for the disgrace, but they disapprove of our publishing the Iranian flag upside down," Azadliq said in an article on Friday.
"This reproach is because of noble feelings: the word Allah is on the Iranian flag."
But the paper insists that the ball is in Iran's court.
"Tehran is adamant that it will not apologise. Therefore it is to blame, not us."
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