(Rewrites throughout with new levels, adds analyst quote)
* Asia ex-Japan shares flat, earnings season to kick off
* China trade data mixed, runs a rare deficit in March
* Easing fear of imminent U.S. attack on Syria
* Bitcoin supported after biggest gains in 4 months
By Hideyuki Sano and Swati Pandey
TOKYO/SYDNEY, April 13 (Reuters) - Asia stocks pared early gains on Friday as caution crept in ahead of the U.S. earnings season and as investors weighed the possible impact on global growth from a tariff spat between the United States and China.
Investors were also left digesting mixed data from China which showed March exports unexpectedly fell 2.7 percent from a year earlier while imports grew more than forecast.
That left the country with a rare trade deficit of $4.98 billion for the month, the first since last February.
China is the world's biggest net crude oil consumer and top buyer of copper, coal, iron ore and soy.
MSCI's broadest index of Asia-Pacific shares outside Japan was up a slim 0.07 percent, having risen as much as 0.5 percent in morning trading.
It is still up about 2 percent on the week.
Chinese shares took a small knock, with both the blue-chip CSI300 index and Shanghai's SSE Composite off 0.4 percent. Hong Kong's Hang Seng index eased 0.1 percent while Japan's Nikkei gained 0.5 percent.
Meanwhile, futures pointed to a weak start for U.S. shares with E-Minis for S&P 500 down 0.3 percent.
The earnings season begins in earnest on Friday with reports from JPMorgan Chase & Co, Citigroup Inc and Wells Fargo & Co.
Analysts expect quarterly profit for S&P 500 companies to rise 18.4 percent from a year ago, in what would be the biggest gain in seven years, according to Thomson Reuters I/B/E/S.
"Our U.S. equity strategists think that this earnings season should be a significant support for equities as companies deliver stronger than expected earnings growth and provide guidance on shareholder return from the tax windfall," analysts at JPMorgan said in a note.
"Our Asia equity strategists agree."
However, trade tensions dominated conversations with analysts at Citi noting prolonged uncertainty will likely hurt open Asian economies such as Taiwan, Singapore and South Korea.
In a change of tack, Trump Thursday asked his trade advisers to look at re-joining the Trans Pacific Partnership, a multinational trade pact he withdrew the United States from early last year.
But he later tweeted that the United States would only join the TPP if the deal were substantially better than the one offered to former President Barack Obama.
"Markets have been pushed around by Trump," said Hiroshi Watanabe, economist at Sony Financial Holdings.
"His modus operandi seems to do anything that seems to be good for his re-election. If protectionism doesn't work, he may switch to international trade," he added.
"Markets are still not yet convinced yet if the U.S. is really re-joining the TPP. But if it does, it's very positive for the global economy and stock markets will like it."
In the currency market, the dollar was a shade firmer at 107.35 yen, edging near to a five-week high of 107.49 touched on April 5.
The yen is sought when investors turn risk averse because Japan's hefty current surplus and massive offshore assets provide protection against the capital outflows deficit-running countries are vulnerable to.
The euro was flat at $1.2328, though on the week it has kept gains of 0.4 percent.
Oil prices edged lower following suggestions from U.S. President Donald Trump that a military strike on Syria may not be imminent. They are still set for their biggest weekly gains since last July.
Brent crude futures were off 20 cents at $71.82 a barrel, not far from Wednesday's high of $73.09. U.S. WTI crude futures slipped 20 cents to $66.89.
Elsewhere, bitcoin fetched $7,968.5 after 14.2 percent gains on Thursday, its biggest gain in four months.
Additional reporting by Swati Pandey; Editing by Shri Navaratnam and Jacqueline Wong