The owner of British Airways endured a bumpy ride in the third quarter as profits took a 162 million euro (£145 million) hit from the slump in sterling and air traffic control strikes.

International Airlines Group (IAG) saw operating profits before exceptional items come in shy of expectations, falling 3.5% to 1.205 billion euros (£1.08 billion) in the three months to the end of September, down from 1.250 billion euros (£1.12 billion) over the same period last year.

The group, which also owns Aer Lingus and Iberia airlines, said total revenues before exceptional items also slipped 4% to 6.486 billion euros ( £5.81 billion) over the period, compared with 6.756 billion euros (£6.06 billion) in 2015.

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Chief executive Willie Walsh said: "While strong, these results were affected by a tough operating environment with a very significant negative currency impact of 162 million euro, primarily due to sterling weakness, and continued disruption due to air traffic control strikes."

He added: "At current fuel prices and exchange rates, IAG expects its operating profit for 2016 to be around 2.5 billion euro (£2.2 billion), and has seen no significant change in its short-term trading conditions."

Passenger revenue dropped 5% to 5.806 billion euros (£5.20 billion) in the third quarter, down from 6.136 billion (£5.5 billion) for the same period in 2015.

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The firm said it had come under pressure in the nine months to September 30, with lower fuel prices only partially offsetting headwinds from Britain's vote to leave the European Union, a string of overseas terror attacks, air traffic control strikes and currency movements.

It said the group suffered "weak trading conditions" in June - both before and after the Brexit vote - with its premium cabins bearing the brunt of the slowdown.

However, it added that it had not faced any "immediate regulatory impact" in the aftermath of the EU referendum result.

IAG announced a new pensions agreement at British Airways on Wednesday, which puts a cap on any extra contributions the carrier could be forced to make.

The move is expected to give BA more room to pay dividends to IAG.

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It came as Mr Walsh warned on Tuesday that the cost of a new runway at Heathrow would "make or break" the project after the Government backed the global transport hub.

He said it was vital that the UK and travelling public "get the benefits from the runway, not the airport's owners".

Shares in IAG were up just under 1% after the third-quarter update.