INTM168070 | Foreign tax paid on trade income: limitation on credit: 1998 legislation
From HM Revenue & Customs · International Manual
The third stage of the legislation, introduced in 1998, applies to foreign interest:
paid on or after 1 January 1999 in respect of amounts paid under arrangements entered into before, and not altered after, 17 March 1998;
paid on or after 17 March 1998 in respect of all other amounts.