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It happened after a man shouted from the House of Lords public gallery during a debate.
The Archbishop of Canterbury was leading the debate when a shout was heard.
Labour peer Lord Giddens, who was speaking, was interrupted by a "continuing disturbance from outside".
A House of Lords spokeswoman said that the Metropolitan Police arrested one man and led him away from the Strangers Gallery, where visitors can watch debates in the House of Lords.
A Metropolitan Police spokesman said: "A man, believed aged in his 20s, was escorted from the premises by officers.
"He was subsequently arrested on suspicion of common assault and criminal damage and remains in custody at a central London police station.
"Enquiries continue."