David Cameron has opened his speech at the Conservative Spring Forum by saying that his party came to power in "perilous" times and that it was "wrestling with historic debts".
He added: "We are here to fight, we are here to win and we have never been more up to the task of turning our country around."
More top news
Police have stepped up patrols after the suspected targeted attacks.
The royal couple will carry out their first official engagements as husband and wife on Tuesday.
Flights from UK airports were an average of 15 minutes late in 2017.