* Abu Dhabi touches highest since 2014
* Banks climb in UAE capital
* Saudi index falls amid Canada row
* Qatar Industries drags down Qatar index
By Tom Arnold
DUBAI, Aug 8 (Reuters) - Abu Dhabi's stockmarket touched four-year highs on Wednesday, helped by bank stocks, while Saudi Arabia's dipped amid a diplomatic row with Canada.
First Abu Dhabi Bank climbed by 0.7 percent. Other banks also rose, with Abu Dhabi Islamic Bank up 1.8 percent and Union National Bank rising by 2.8 percent.
Banks are expected to be among the beneficiaries of a 50 billion dirham ($13.6 billion) plan announced by Abu Dhabi in June to revitalise the economy.
The Abu Dhabi index closed 0.3 percent up, after hitting its highest level since late 2014 in earlier trading.
In Saudi Arabia, PetroRabigh, a joint venture between Saudi Aramco and Japan's Sumitomo Chemical, tumbled by 8.2 percent after it announced a 25.6 percent fall in second-quarter net profit on Tuesday.
The Saudi index ended 0.4 percent lower as investors worried about the fallout from a diplomatic dispute between Saudi Arabia and Canada. The dispute, over Canadian support for jailed rights activists, threatens to hurt bilateral trade which largely consists of Saudi exports of petrochemicals, plastics and other products.
Dubai's index was weighed down by Emirates NBD, which fell by 1.0 percent. Deyaar Development was down by 5.8 percent.
Drake & Scull was down by 9.9 percent. The company has been lagging because of concerns about its financial position, business outlook and the outcome of an investigation by United Arab Emirates authorities into financial violations by previous management.
The Dubai main index ended 0.1 percent lower.
In Qatar, Industries Qatar was the main drag on the index, falling by 1.6 percent. After the market closed, the company - the Middle East's second-biggest petrochemicals firm - reported a rise in profit to 2.51 billion riyals ($689.5 million) for the first half of 2018, up from 1.61 billion riyals in the same period a year earlier.
The index fell 0.1 percent.
* The index slipped 0.4 percent to 8,210.3 points.
* The index edged down 0.1 percent to 2,949 points.
* The index gained 0.3 percent to 4,926 points.
* The index lost 0.1 percent to 9,962 points.
* The index rose 0.2 percent to 5,466 points.
* The index lost 0.2 percent to 1,346 points.
* The index went down 0.3 percent to 4,436 points.
* The index rose 0.6 percent to 15,8623 points. ($1 = 3.6728 UAE dirham) ($1 = 3.6405 Qatar riyals) (Reporting by Tom Arnold; Editing by Mark Trevelyan)