Claims are still being made that oil, amongst other products such as alcohol, are being smuggled from northern Iraq to Iran.
The accusations that petroleum is consistently being smuggled over the mountainous border in the north at Haj Omran and to the north east of Iraq at Penjuin are denied by the Kurdistan Regional Government (KRG), that is autonomous from Baghdad.
It has been said that hundreds of millions of dollars worth of crude oil and refined products are illegally transported over the border to Iran annually.
However, the proliferation of fuel trucks at border points such as Penjuin raises the accusation, often backed by truckers themselves, that US-promoted international sanctions on Iran to prevent key products reaching the country are being bypassed.
Other people have claimed that smuggled oil is coming from central Iraq rather than the north, to Iran.
Recently, at Haj Omran fuel trucks travelled through the region but at far less frequency than might be expected on a trade route between two countries.
Several tanker trucks were parked up a couple of miles from the border point, as shown in the following two photos.
At Penjuin, having been given a talking to by security at the border for my presence there, I was unable to stop and talk to the scores of truckers that were parked in a dusty plain about a five minute drive from the border point.
However, I did get some brief footage of the scores of tankers parked there and many more lining up minutes from the border, where they waited to cross into Iran.
The KRG said that some tankers legally carried oil to Iran, causing a dispute with Baghdad which was unhappy about the KRG independently signing contracts, before such deals were stopped by the government in the north.
But claims persist that smuggling is continuing, with great benefit to people both sides of the border.
Follow Rhodri Davies on Twitter: @rhodrirdavies