WASHINGTON, May 17 (Reuters) - The White House said on Wednesday it was concerned al Qaeda is establishing a presence in Somalia but would not say whether Washington is backing Somali warlords fighting Islamic militants there.

Militia battles have been waged over the past week between militants linked to the Islamic courts, which have imposed order on parts of Mogadishu through traditional Islamic law, and a self-styled anti-terror alliance of warlords.

Asked whether Washington was working with the so-called anti-terror alliance of warlords, White House spokesman Tony Snow said "there is concern about the presence of foreign terrorists, particularly Al Qaeda, within Somalia right now.

"In an environment of instability, as we've seen in the past, al Qaeda may take root, and we want to make sure that al Qaeda does not in fact establish a beachhead in Somalia," Snow said.

Americans have bad memories of U.S. involvement in Somalia. On Oct 3 and 4, 1993, 18 U.S. soldiers were killed and 79 injured in a battle in Mogadishu with Somali guerrilla fighters loyal to warlord Mohamed Farrah Aidid.

As for the current situation, Snow said "the terrorists are going to seek to take advantage of the environment and use that kind of chaos in order to put together camps and therefore mount operations around the world."

"We will continue to work with regional and international partners wherever we can to crack down on terrorism and also to try to prevent its rising," he added.

He also said Somalia needs a functioning government and that Washington support transitional federal institutions there that are trying to re-establish a central government that can end the civil conflict.