Spanish police repeatedly charged separatist demonstrators at the entrance to Barcelona's El Prat airport Monday as they protested a Supreme Court ruling that jailed nine of their leaders, an AFP correspondent said.

Thousands of demonstrators headed to the airport in a bid to block access to the terminal following the court ruling, which saw their leaders handed heavy prison terms over the failed 2017 independence bid.

According to an AFP correspondent at the scene, several hundred people were locked in a standoff with police, hurling stones and rubbish bins at them.

Thousands of protesters followed an online call to march in the airport after the convictions were announced
Thousands of protesters followed an online call to march in the airport after the convictions were announced AFP / LLUIS GENE

When they repeatedly tried to break through the cordon to get inside the terminal building, police charged at them each time, the correspondent said.

A regional police spokesman confirmed the clashes, saying the officers had held off "people who were trying to cross the police line" to get inside.

According to national airports operator AENA, "around 20 flights were cancelled" after demonstrators blocked off access to El Prat, briefly cutting rail links and causing huge tailbacks on roads leading to the airport.