U.N. leader Ban Ki-moon said Tuesday it was a "disgrace" that there is no global arms trade regulation as he opened treaty talks held up by Palestinian demands for a place in the negotiations.

The 193 U.N. members have until July 27 to hammer out a deal for a treaty on dealing in conventional weapons, which experts estimate to be worth more than $70 billion a year.

The United States will release about $1.1 billion to Pakistan's military as part of a deal that will see Islamabad lift a blockade on NATO supply convoys into Afghanistan, a U.S. official said Tuesday.

The money, from a U.S. "coalition support fund" designed to reimburse Pakistan for the cost of counter-insurgency operations, had been withheld due to tensions between the two countries and Islamabad's closure of the supply routes.

Pakistan is reopening key supply routes into Afghanistan closed since November, U.S. Secretary of State Hillary Clinton said Tuesday, adding the U.S. was sorry for the loss of life in an attack last year.

During a telephone conversation Tuesday with her Pakistani counterpart Foreign Minister Hina Rabbani Khar, she "informed me that the ground supply lines into Afghanistan are opening," Clinton said.

French police searched Nicolas Sarkozy's offices and home Tuesday as part of their probe into suspected illegal financing of his successful 2007 presidential election campaign, his lawyer said.

Magistrates are investigating claims that staff for Liliane Bettencourt, heiress to the L'Oreal cosmetics empire and France's richest woman, gave envelopes stuffed with cash to Sarkozy aides to finance the campaign.

Three weeks of U.N. talks aimed at hammering out a draft treaty to regulate the $70 billion a year global arms trade finally got under way on Tuesday, a day late because of a diplomatic tussle over Palestinian representation.

"It is with great pleasure that I declare open the U.N. conference on an arms trade treaty," said U.N. leader Ban Ki-moon.

French Prime Minister Jean-Marc Ayrault on Tuesday reiterated his government's determination to prevent groups like al-Qaida setting up "international terror bases" in rebel-held north Mali.

"Our determination will be total in preventing groups like AQIM (Al-Qaida in the Islamic Maghreb) setting up international terror bases that threaten the peace and prosperity of the whole region and our security too," he said.

France said Tuesday it was confident that the United Nations Security Council would soon pass a resolution authorizing a west African force to fight rebels holding northern Mali.

"We are confident it will be adopted," said Foreign Minister Laurent Fabius.

Technical experts from Iran and major world powers gathered Tuesday in Istanbul for closed door talks on Tehran's disputed nuclear program, a European diplomat said.

The meeting between nuclear physics experts from Iran and the major powers known as P5+1 -- the five permanent members of the U.N. Security Council and Germany -- takes place without the participation of diplomats, the source said.

Iran accused world powers on Tuesday of dragging their feet in negotiations over its nuclear activities, as both sides were about to hold a new, downgraded round of talks in Istanbul.

Foreign ministry spokesman Ramin Mehmanparast told a weekly briefing that, if the powers ignored Iran's nuclear "rights" and failed to bargain on equal terms, the negotiations could lead to an "impasse".

Russian Prime Minister Dmitry Medvedev on Tuesday made a repeat trip to one of the four Pacific Kuril islands claimed by Japan, drawing new protests from Tokyo following years of unrelenting tensions.

Medvedev arrived on the island of Kunashir which lies just north of Japan's Hokkaido Island, pledging to improve the lives of the disputed chain's residents.