DUBAI, July 19 (Reuters) - The United Arab Emirates" de facto ruler held talks in the Saudi capital Riyadh on Monday with Saudi Crown Prince Mohammed bin Salman, at a time of tensions between the two Gulf allies that led this month to an open standoff over oil policy. "My brother Mohammed bin Salman and I discussed ways to further deepen the fraternal bond and strategic cooperation between our nations. The partnership between the UAE and Saudi Arabia continues to be strong and prosperous," Abu Dhabi Crown Prince Mohammed bin Zayed al-Nahyan tweeted. A public dispute between the two states this month disrupted policy setting by OPEC+, an oil producers" group that comprises OPEC and a number of allies. On Sunday, OPEC+ secured agreement to boost oil supplies after the two Gulf producers reached an understanding. read more Analysts say increasing economic competition is laying bare differences between Saudi Arabia and the UAE as the kingdom tries to challenge its smaller neighbour"s dominance as the region"s business, trade and tourism hub.