From Atiq Sharif

February 1 (Reuters) - The Saudi stock market closed lower on Sunday, as concerns that the United States might take military action against Iran highlighted the risks that the region would face most as a result of any Iranian response.

Iranian Supreme Leader Ayatollah Ali Khamenei was quoted by state media today as saying that any US attack on Iran would turn into a regional conflict, as tensions between Washington and Tehran escalate.

The United States has increased its naval presence in the Middle East after US President Donald Trump repeatedly warned Iran that he might intervene if it did not reach a nuclear agreement or if it continued to kill protesters.

The Saudi index fell 1.9 percent, its biggest one-day drop since April, weighed down by a 9.5 percent decline in shares of Saudi Arabian Mining Company (Ma'aden).

Shares in Saudi oil giant Aramco fell 2.4 percent.

The Saudi index had risen more than 10 percent from January 7 to the end of the same month after the country announced it would fully open its financial markets to all foreign investors starting February 1.

The Qatari index rose 0.3 percent, supported by a 1.5 percent increase in shares of Qatar National Bank, the largest bank in the Gulf region by assets.

The Qatari Foreign Ministry said in a statement on Saturday that Qatari Prime Minister Sheikh Mohammed bin Abdulrahman Al Thani met with the Secretary-General of Iran’s Supreme National Security Council, Ali Larijani, in Tehran and they reviewed efforts to ease tensions in the region.

Bahrain's main index closed 0.2 percent higher, while Kuwait's main index closed 1.1 percent higher. Oman's main index ended the day down 1.3 percent.

Outside the Gulf region, Egypt's blue-chip index lost 0.3 percent.