* TSX futures up 0.4%

April 22 (Reuters) - Futures for Canada's main stock

index edged higher on Wednesday after U.S. President Donald

Trump extended the ceasefire with Iran indefinitely, though

doubts lingered following reports of gunfire attacks on

container ships in the Strait of Hormuz.

June futures on the S&P/TSX index were up 0.4% at

5:13 a.m. ET (1013 GMT).

* Trump said the U.S. had agreed to a request by Pakistani

mediators "to hold our attack on the country of Iran until such

time as their leaders and representatives can come up with a

unified proposal."

* Oil prices were up with Brent trading above $100 a barrel,

erasing earlier losses following reports of gunfire attacks on

at least three container ships in the Strait of Hormuz.

* Spot gold and silver prices also rose 1% and

1.9% respectively following the extension of the ceasefire.

* Markets also weighed trade uncertainty after Canada's

chief negotiator to the U.S. said resolving all issues under the

North American trade pact by a July 1 review deadline was

unlikely.

* Investors will also monitor corporate earnings in the U.S.

and Canada to gauge how companies are tackling headwinds from

the Iran war.

* The Toronto Stock Exchange's S&P/TSX Composite Index

posted its biggest daily decline in a month on Tuesday

as investors priced in some uncertainty related to the war.

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