LONDON - There is "very, very credible" intelligence that militants are planning an imminent attack on those gathering at Kabul airport in an attempt to flee Afghanistan, British armed forces minister James Heappey said on Thursday.

"There is now very, very credible reporting of an imminent attack, and hence why the Foreign Office advice was changed last night, that people should not come to Kabul Airport, they should move to a safe place and await further instructions," Heappey told BBC radio.

"I can only say that the threat is severe. We will do our best to protect those who are there. There is every chance that as further reporting comes in, we may be able to change the advice and process people anew, but there is no guarantee of that."

(Reporting by Michael Holden and David Milliken; Editing by Kate Holton) ((michael.holden@thomsonreuters.com; +44 207 542 3213; Reuters Messaging: michael.holden.thomsonreuters.com@reuters.net))