* U.S. Treasury says clear Assad govt under financial strain
* More than 55 countries working to beef up sanctions on Syria
By Rachelle Younglai
WASHINGTON, June 6 (Reuters) - The United States, Saudi Arabia and dozens of other countries agreed on Wednesday that further economic sanctions were needed to stop President Bashar al-Assad from repressing Syrian people and urged nations to adopt an arms embargo, travel bans and tougher financial penalties against his government.
"A continued concerted multinational approach is necessary to further deprive the Assad regime of the financial resources needed to sustain its campaign of violent repression," the Friends of Syria working group said at the end of a one-day meeting in Washington that was hosted by the U.S. Treasury.
More than 55 mostly Western and Arab countries opposed to Assad's rule said that at a minimum an asset freeze on senior Syrian government officials as well as restricted business with Syria's central bank and leading commercial bank was needed to isolate his regime from the global financial system.
The group also expressed support for taking steps toward a United Nations Security Council "Chapter 7" resolution - a measure that could authorize the use of force.
A peace plan brokered by international envoy Kofi Annan has so far failed with Assad's government refusing to honor a comprehensive ceasefire. Troops loyal to Assad are accused by opponents of a new massacre of at least 78 people hours before a divided United Nations Security Council convenes to review the crisis.
"Absent meaningful compliance by the regime with the Annan plan, that is the direction in which we are soon headed," U.S. Treasury Secretary Timothy Geithner told delegates at the beginning of the meeting.
Later, a U.S. Treasury official said there were a couple of major components to their strategy, which included stripping away Assad's supporters, putting pressure on the Syrian business community and starving Assad's government of resources needed to survive.
The official did not have an estimate for the level of Assad's reserves or for how long he could survive. But he said it was clear the Syrian government was under financial strain and pointed to the significant deterioration in Syria's currency and the European oil embargo that accounted for 90 percent of the country's export market.
"It is clear that they are depleting their reserves," the Treasury official said.
The United States has blocked Syria's central bank and top Syrian government officials from U.S. markets. Qatar, which co-chaired the working group with Turkey, has imposed similar penalties on Syria's financial institutions. Turkey has expanded its list of blacklisted government officials and the European Union has banned imports of Syrian oil and imposed sanctions on Syria's main mobile phone operator.
Earlier, Geithner acknowledged that the sanctions would not be enough to stop the violence or bring about political change but said they played an important role.
"Strong sanctions make clear to the Syrian business community and other supporters of the regime that their future is bleak so long as the Assad regime remains in power," he said.
The working group, which included representatives from the European Union, South Korea and Japan, discussed how the government has tried to evade sanctions and how they could further coordinate their penalties. Foreign ministers of the Friends of Syria, including U.S. Secretary of State Hillary Clinton, are currently meeting in Istanbul for a conference on Syria.