Niall Horan has just flown home from One Direction's first headline tour of the US

Niall Horan has apologised for swearing at One Direction fans who were waiting for him at Dublin Airport earlier this week.

The 18-year-old singer called the crowd of waiting Directioners a 'shower of c**ts' as he walked through the terminal in his home country of Ireland.

'really sorry if I caused any offence. It was just banter with fans who I think of more as mates,' Tweets Niall.

'but I understand that it's not a word I should be using at all.'

There was one person in particular who wasn't impressed with Niall's bad language - band mate Harry Styles' mum Anne Cox.

She wrote a Twitter message earlier today calling the word 'horrid'.

But Anne later reassured 1D fans that that she'd forgiven her son's friend.

'I didn't comment about him, just about the word. I love @NiallOfficial,' she Tweeted.

SEE VIDEO Niall Horan swears at One Direction fans...

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