Britain's Davis Cup tennis team have delayed their departure to Belgium by 24 hours after Brussels went on maximum alert amid a search for armed Islamist extremists and fears of imminent attacks.
A spokesman for the Lawn Tennis Association said the team, led by Andy Murray, had trained on the clay courts at London's Queen's Club on Monday now planned to travel on Tuesdsay.
The LTA said in a statement it was monitoring the situation closely and taking government advice.
"The safety of everyone in the British contingent, including our players and fans, remains our number one priority," it added.
The three-day final between Britain and Belgium is scheduled to start on Friday at the 13,000-seat Flanders Expo in Ghent, 50km north west of Brussels.
The Flemish Tennis Federation (FTF), who are staging the event, said it believed the final would be played.
"Everything is continuing because we believe it will go on," the FTF was quoted as saying by the BBC.
FTF chief executive Gijs Kooken is in regular contact with the Belgian government and said he had "not yet had a signal that it's not safe to organise the event.
"It is an event with international exposure, with 13,000 spectators a day, so it is a risk event, of course, in the current situation - but I'm very confident in our government.
"Of course, you never can predict what will happen next, but I would be surprised if it was cancelled. I'm quite confident that we will play next weekend," he told the BBC.
Belgium put the capital on maximum security alert on Saturday, shutting the metro and warning people to avoid crowds because of a "serious and imminent" threat of coordinated, multiple attacks by militants.
The move follows last week's deadly attacks in Paris by Islamic State militants, of whom one suspect from Brussels remains at large.
Bernard Clerfayt, mayor of the Brussels district of Schaerbeek, was quoted by broadcaster RTBF as saying there were "two terrorists" in the Brussels area ready to carry out violence.
The International Tennis Federation (ITF) said it was greatly concerned by the raised terror alert but preparations for the final were continuing.