Outside the Houses, teenagers chanted loudly "Peace now" and "No war" as black cabs and red London buses jockeyed to pass through the narrow road round the Parliament Square.

Police were forced to drag some youngsters out of the road as their banner-waving campaign temporarily brought traffic to a grinding halt, witnesses said.

One man was arrested for breach of the peace in a separate protest outside Foreign Secretary Jack Straw's London home earlier Wednesday.

"There was some disturbance and noise and one person was arrested, but there was no major riot," said Mick Mills, chief inspector of Leicestershire Police.

Nick Buxton, organizing the protest outside Straw's house, said,"We got the message across that the war is going to have a very huge humanitarian impact and people are angry about this war."

The protesters blocked roads near Straw's house and staged a "die in", saying they had delayed his departure to work by half an hour.

Across Britain, children were abandoning lessons to campaign against the imminent war, with 20 pupils facing suspension from Cape Cornwall School in St. Just, Cornwall, for walking to Penzance on Tuesday.

The Stop the War Coalition says hundreds of thousands of anti-war campaigners will pound the streets of London in a mass protest against war on Iraq this weekend.

The group is also calling on workers to down tools as soon as war breaks out.

"It is now the settled view of the British people that this war is unnecessary and we do not wish our troops to be involved in such an action," said Stop The War Coalition chairman Andrew Murray.

(Xinhua News Agency March 20, 2003)