SINCE it made peace with Israel in 1979, Egypt has been the United States' most important ally in the Arab world. But the US-Egyptian relationship has lately developed cracks -- rifts that Egyptian President Hosni Mubarak hopes to close during a current five-day visit to the US.
US officials have been irked by Egypt's reluctance to back the extension of a 1968 treaty to halt the spread of nuclear weapons and by Egypt's close friendship with Libya -- two issues on an agenda that will also include the Middle East peace process and the perennial problem of how to deal with Iran and Iraq.
Mr. Mubarak's main interest will be Republican lawmakers, who are eager to cut foreign aid -- of which Egypt now gets $2 billion annually -- and to tie what remains of the aid more closely to US interests abroad. ''Mubarak needs to renew his ties with the Hill,'' says one Clinton administration official. ''That's worth a trip across the Atlantic.''
One US interest the administration and lawmakers hold dear is the Nuclear Non-Proliferation Treaty (NPT), which has put Washington and Cairo at odds. The US is trying to convince a majority of the 172 signatories to support a permanent extension of the NPT when it comes up for review at a conference in New York starting April 12th. The NPT commits states that do not have nuclear weapons not to acquire them and those that do, to eventually eliminate them.
In an interview Thursday, a senior Egyptian diplomat said Egypt supports the NPT and will make no effort to block its extension. But he reaffirmed Egypt's intent to make its own vote for extension contingent on a commitment by Israel to abandon its nuclear program, which has allegedly produced an estimated 300 warheads. Egypt's goal is to ''persuade Israel in a friendly manner that the time is right now for certain concrete steps'' to phase out its nuclear program, says Ossama el- Baz, a top Mubarak aide and first undersecretary in Egypt's foreign ministry.
''Israel can't phase out overnight. We're not asking them to do it today, all at once,'' Mr. El-Baz says. But if Israel continues to build nuclear weapons ''it could give justification for other states in the region to follow suit.''
US officials say Egypt's position is a nonstarter as long as Israel's main enemies -- Iran, Iraq, and Libya -- remain intent on developing nuclear weapons.
''Egypt is willing to support and lobby for supporting extension of the treaty if Israel gives us reason to believe that it will seriously move towards joining the treaty,'' El Baz says. ''How will Egypt vote [at the NPT conference]? We have not made up our mind. We're looking for signals about which way Israel is going.''
Mubarak's position has displeased Israel's friends in Congress, who hold the foreign-aid purse strings. His visit is also likely trigger protests from the families of 188 Americans killed in the 1988 bombing of Pan Am Flight 103 over Scotland.
They, and influential congressional backers, are angry that Egypt has been a conduit for embargoed goods to Libya, which is accused of complicity in the incident, and that the US has not leaned harder on Egypt to desist.
Mubarak has regularly made the case for lifting international sanctions against Libya and for allowing two Libyans accused of the bombing to be tried in a neutral venue -- not in Scotland or the US, as the US insists.
Last year, according to El-Baz, Egyptian officials considered recommending to Libyan leader Muammar Qaddafi that he turn the two over for trial in the United States or Scotland. They abandoned the idea after lawyers for the two -- including two Scots and two Americans -- convinced them during a seven-hour meeting in Cairo that the Libyans would not receive a fair trial in either country.
The issue has posed a dilemma for the Clinton administration that last month -- more than three years after the two Libyans were indicted -- posted a $4 million reward for their capture and announced plans to ask the United Nations to add oil to the Libyan embargo.
The US is eager to keep pressure on Libya but is mindful of the benefits that have accrued to Egypt for its diplomatic support of Libya. Mr. Qaddafi has accepted hundreds of thousands of Egyptian guest workers into Libya, easing high rates of unemployment that have nourished Muslim extremism in Egypt.
Relations with Cairo were boosted recently when Mubarak and Vice President Al Gore, on a visit to Cairo, announced a joint initiative to stimulate Egypt's private sector, attract foreign investment, and reduce unemployment. Mubarak's return visit to the US will extend the warming trend, Egyptian officials predict. ''There is basically a positive inclination towards Egypt'' in the US, says El-Baz.