(Reuters) – Kuwait’s National Aviation Services (NAS) said on Friday it had increased its stake in John Menzies for 32.1 million pounds ($43.61 million), taking its total ownership to about 19%, weeks ahead of a deadline to make another takeover offer for the British airport services group. The Kuwaiti suitor said it bought another 5.8% stake of John Menzies at 605 pence per share. NAS on Thursday became John Menzies’ top shareholder, a week after the 188-year-old Edinburgh-based company rejected a lower proposal. Under British regulations, NAS’ future offers for the London-listed firm have to…