BENGHAZI, Libya - The visiting US assistant secretary of state Jeffery Feltman on Tuesday said that at the invitation of US president Barack Obama, the Libyan opposition will establish a representative office in Washington.

"This step marks an important milestone in our relationship with the National Transitional Council," Feltman told the reporters at a press conference at the end of his visit in Libyan opposition's base Benghazi.

Feltman reiterated that the Libyan Leader Muammar Gadhafi had lost legitimacy to rule, calling him to step down immediately and allow the Libyan people to determine their own future.

He delivered a message from Obama, saying the US is committed to protecting the civilians in Libya.

"President Obama also underscored the US commitment to work with our international partners to support the National Transitional Council and efforts for democratic institutions, and he stressed the US will continue to focus on finding ways to improve the National Transitional Council's financial situations," said Feltman.

Feltman was in Benghazi for talks with the opposition leadership during a three-day visit from Sunday to Tuesday. He said he has held talks with the National Transitional Council leader Mustafa Abdul Jalil and representatives from various groups.

The opposition is now seeking and gaining more international support in its fight against Gadhafi's government. Following Polish Foreign Minister Radoslaw Sikorski and the European Union high representative of foreign and security policy Catherine Ashton, Feltman is another high-ranking diplomats who visited the opposition's base.