The British Foreign Office on Thursday advised its citizens to avoid "all but essential" travel to Zimbabwe due to tensions surrounding last month's elections.

"We advise against all but essential travel to Zimbabwe at this time due to the continuing tension surrounding the election and the deployment of uniformed forces... and war veterans around the country," said a statement.

"The current situation is unpredictable, volatile and could deteriorate quickly, without warning."

It advised travellers to the country to "keep a low profile, exercise a high degree of caution, monitor local news reports and avoid all areas where demonstrations may be held, or where there are large gatherings of people."

The Swedish government on Friday also advised Swedes to avoid "non-essential" trips to Zimbabwe due to tensions following last month's elections there.

"In light of the tense situation, the Foreign Ministry warns for the time being against all non-essential travel to Zimbabwe," the ministry said in a statement.

International concern has grown about violence after the disputed March 29 election, the results of which have yet to be announced.

Opposition leader Morgan Tsvangirai claimed victory after the first round, but the party of President Robert Mugabe, in power for the past 28 years, has said no one won and has called for a second voting round.

AFP