Tourism authorities for, and operators to, all three destinations were finalising the promotional campaigns this week, with a combined spend approaching £100m.
The US, whose tourism industry has been depressed since the terrorist attacks of 2001, has a marketing war-chest of $50m (£30.2m) to take advantage of a recent upsurge in interest in US travel.
Its tourism body, Visit USA, said web site and phone enquiries had seen "a really marked kick" over the past month. It plans a wide range of activities, possibly under the 'See America' theme.
Alan Waddell, Visit USA's director of development for the UK, said it is not certain what proportion of the grant will be spent on the UK market, but is keen to take advantage of a strong exchange rate and post-war empathy between the two countries.
Meanwhile, Kenyan specialist tour operator Somak Holidays expressed delight at the decision by the Foreign and Commonwealth Office (FCO) to lift the six-week-long warning on travel to the country last week.
The warning mentioned an 'imminent' terrorist threat, which grounded direct British Airways flights and cut tourism numbers. Losses to Kenyan tourism totalled more than £18m.
Somak and other operators are planning to launch special offers to kick-start demand, while a BA spokeswoman said the airline would resume operations this week.
Operators are lobbying the Kenyan authorities to maximise its budgets for a major campaign stressing the destination's safety.
Leading operators to China are also set to pursue aggressive marketing strategies after the FCO gave the country the all-clear last week. The outbreak of SARS in March stymied a promising tourism year.
Bales Worldwide, Kuoni and Thomas Cook Signature are preparing initiatives including two-for-one deals and promotional campaigns.
The Chinese government is understood to be considering running a multi-million-dollar tourism campaign after estimates that SARS will cause a 50% slump in tourism for 2003, costing £1.15bn.