A jet belonging to forces loyal to Syrian President Bashar Al-Assad is seen flying in the sky of Aleppo (Reuters)

A North Korean plane heading for Syria suspected of carrying weapons to help President Bashar al-Assad violent repression of the rebel upspring, has been blocked by Iraq.

An Iraqi senior official confirmed Iraq denied the plane permission to flight through its airspace because of its suspicious cargo, Reuters reported.

"Continuing the Iraqi government policy to investigate the passing of weapons to Syria through Iraqi land and air space, the Iraqi authorities prevented a North Korean plane from going to Syria, after they suspected that the plane was shipping weapons," Ali al-Mossawi, media advisor to the Iraq's prime minister, told Reuters.

Alongside China, Russia and Iran, North Korea is still supporting the Assad regime in the civil war that has laid waste to Syria apart in the last 18 months.

In June a UN report revealed North Korea attempted several times to ship weapons to Syria in the last year, defying international sanctions against such trade.

Later this year North Korean state media said the country's leader Kim Jong-Un had received a message from Assad thanking him for the support provided, the Lebanese newspaper The Daily Star reported.

"I would like to express my deep thanks to your Excellency [...] for having rendered support and encouragement to our just cause against the moves of the world powers to interfere in our internal affair," the message reportedly read.

Iraq has previously been accused of allowing the passage over its territory of Iranian planes delivering weapons shipments to the Syrian regime.

According to an US intelligence report, Iran has been flying civilian aircraft carrying military personnel and weapons to Syria across Iraq.

Iraq rejected the allegations.