JOHANNESBURG, Jan 31 (Reuters) - South Africa's rand

weakened on Friday against a buoyant dollar as markets awaited

U.S. President Donald Trump's tariff deadline for Canada and

Mexico.

At 1447 GMT, the rand traded at 18.6350 against the dollar

, about 0.1% softer than its previous close. The dollar

last traded about 0.2% firmer against a basket of

currencies.

Trump has said he will impose 25% tariffs on imports from

Mexico and Canada from Feb. 1 if the two countries do not crack

down on the flow of illegal migrants and the drug fentanyl into

the United States.

South Africa's central bank said on Thursday that it had

modelled the potential impact of a trade war, as it highlighted

the uncertain global backdrop while trimming interest rates.

On the Johannesburg Stock Exchange, the Top-40 index

was last up about 0.4%.

The benchmark 2030 government bond slipped, with

the yield up 5 basis points to 9.055%.