JACOB Rees-Mogg has said the Union Flag flying outside of Portcullis House in London is "deeply troubling" after reports that it has been put up incorrectly.

In the Commons earlier, Tory MP Robert Courts told the Leader of the House the flag had been flying upside down at the offices for weeks now.

Rees-Mogg demanded the error is corrected, as the Union Flag being flown upside down signifies a distress signal.

Whether a Union Flag is being flown the correct way up can be established by looking towards the flagpole. The half of the flag nearest the pole should be above the red diagonal stripe.

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Courts said: "I wouldn't want to be seen to be too much of a stickler for these things, but... the Union Jack above Portcullis House has been flying upside down for some time now.

"This could be a mistake. I doubt that the building has surrendered to anybody, but could we have the debate in government time as to whether in fact the building is in distress or whether its the MPs within it that are in distress?"

Rees-Mogg replied: "I'm sorry that this has happened, I'm glad it's been brought to the attention of the House authorities, I imagine that someone is, as we are speaking, going to correct this because I see the clerk of the House of Commons is taking action immediately and things do sometimes happen swiftly and I assure you that members of Parliament are not in distress."