Four cars were used to block both carriageways on the bridge

The protesters used four cars to block both carriageways on the bridge at 1400 GMT.

But some motorists became angry and tried to move them out of the way.

Tim Stimson, from Hull Stop the War, said the situation was "not ideal."

No arrests

He said: "It's not something we want to make a habit of doing.

"If only they would start listening. We are not a minority fringe."

The protest lasted 20 minutes before the cars were driven away.

No arrests were made but police said they would not put up with such behaviour in future.

David Frost, from Humberside Police, said: "We are not going to tolerate people being held up in this manner.

"If this sort of thing happens again they will be dealt with, and arrested."