As Egyptian President Abdel Fattah al-Sisi begins his second term, a new chapter in Egyptian-Russian relations is being written. Disappointed by U.S. policy, Cairo has strengthened its ties with Moscow. The new trajectory stems in part from the lack of robust American engagement, which has left an open door for Russia to make inroads at Washington’s expense.

Last month, Egypt and Russia signed a 50-year agreement in Moscow to establish a Russian Industrial Zone (RIZ) in the Suez Canal Economic Zone (SCZone), an ambitious economic development project initially launched by al-Sisi in 2014. Egypt hopes that the RIZ project, signed during the 11th meeting of the joint Egyptian-Russian commission, will attract up to $70 billion in investments and create 35,000 jobs. The Russians plan to use the RIZ to manufacture a vast array of goods including heavy trucks and engines. For Moscow, which faces continued U.S. and EU sanctions, the project would provide an access point for exporting goods to overseas markets—especially to the Middle East, Africa, and Latin America.

The RIZ is not the first sign of deepening ties between Russia and Egypt. In his second visit to Cairo since Abdel Fattah al-Sisi came to power this past December, Russian President Vladimir Putin presided over the signing of a nuclear power plant deal that includes a $25 billion loan from Moscow. The Dabaa nuclear plant, with four reactors and a capacity of five gigawatts, is scheduled for completion by 2029, according to Russia’s state-owned nuclear operator Rosatom.

In April, Moscow also resumed civilian flights to Egypt after an Islamic State affiliate bombed a Russian Metrojet flight in 2015, killing 224 people. The flow of Russian tourists to Egypt had subsequently stopped, damaging Egypt’s struggling tourism industry. Direct flights from Russia to Egypt’s main tourist resorts—Hurghada and Sharm el-Sheikh—have yet to resume. However, after talks on May 14 with his Egyptian counterpart Sameh Shoukry, Russia’s Foreign Minister Sergey Lavrov said that continuing close cooperation with Egypt on security issues was hastening the resumption of direct air link to the Red Sea resorts.

These specific developments reflect the general warming trend in a relationship between Cairo and Moscow that has deepened over the past few years. Egyptian exports to Russia rose by some 26 percent in 2017, reaching a record $3.8 billion, and the Russia-Egyptian Business Council claims bilateral trade could increase from $6 billion to $10 billion in 2018. In the energy sector, Russian oil giant Rosneft bought a 30-percent stake in Egypt’s Zohr gas field for $1.125 billion last year, becoming a key player in developing one of the largest gas deposits in the Mediterranean Sea. Further, Rosneft and Fleet Energy signed a framework agreement in late May to explore a joint venture for providing gas supplies to Egypt.

Since 2014, Egypt has been increasingly turning to Russia for arms sales. The decision to do so was initially triggered by al-Sisi’s disappointment with Washington after the 2013 removal of Islamist President Mohammed Morsi’s regime. When the Obama Administration halted the delivery of previously contracted weapons systems including F-16 fighter jets and AH-64 Apache attack helicopters, and canceled joint military exercises between Egyptian and American armed forces, al-Sisi and Putin started to talk. And the disappointment did not end with Obama’s term in office. Despite apparently warm personal relations between al-Sisi and President Donald Trump, in August 2017 the Trump Administration decided to condition economic and military aid over Cairo’s track record towards human rights, democracy, and rule of law. With all that as a backdrop, Russia has stepped up to fill the void, with several arms deals worth billions of dollars signed during al-Sisi’s presidency. 50 MiG-29 fighter jets were purchased in 2014 and delivery started late last year. Egypt also purchased 46 of a naval version of the Kamov Ka-52 Alligator helicopter, intended for the two French Mistral helicopter carriers that Cairo bought from Paris in September 2015. (France originally built the two ships for Russia, but canceled the sale after Moscow’s invasion and annexation of Crimea.)

The military developments go beyond arms sales, with strategic cooperation increasing as well. In November 2017, the two countries inked an agreement during a visit by the Russian Defense Minister to Cairo that allows for the joint use of each other’s airspace and military airbases. The five-year deal, which could be extended further if both parties agree, has raised eyebrows in Washington. If implemented, it would reinforce Russia’s military presence in the Middle East and create a potential launching pad for wider Russian operations in North Africa.

The countries’ militaries have also held several joint exercises in that time period. In 2015, Russia and Egypt held joint naval drills off the Mediterranean Egyptian port of Alexandria. In 2016, Egyptian and Russian paratroopers participated in a joint military exercise titled “Defenders of Friendship,” the first of its kind in Africa, which was followed by a similar exercise in Russia in 2017. Egypt will again host Russian and Egyptian paratroopers in 2018, according to the Russian Ministry of Defense.

And finally, Egypt and Russia increasingly share common views on regional issues. On Syria, both countries have been calling for preserving the country’s territorial integrity and its national army. In October 2017, the two countries brokered a ceasefire deal in southern Damascus. In Libya, the two countries support the Libyan National Army, which is led by Khalifa Haftar, the military commander who dominates eastern Libya. In addition, the airspace deal with Egypt could bring Russia closer to Libya and raise the likelihood of greater Russian military involvement there.

With the election of President Donald Trump, al-Sisi hoped for better relations with Washington to maintain stability and address the country’s economic challenges. Clearly this has not yet materialized. On the one hand, visible warming of ties with a geopolitical rival of the United States is a game that Egypt is well versed in. The Trump Administration should proceed carefully and unemotionally.

But given the deteriorating situation in the broader Middle East and Russia’s rush to capitalize on it to cement itself as a stakeholder in the region, there is no excuse for the United States passively sitting on the sidelines. The Trump Administration should ramp up engagement with the Egyptians to address lingering concerns and try to move the relationship forward where possible. The Senate should take up the nomination of David Schenker as Assistant Secretary of State for Near Eastern Affairs, and the Trump Administration ought to nominate a U.S. Ambassador to Egypt as soon as possible. Without diplomatic talent on the ground, Washington risks ceding hard-won influence in the region without putting up the slightest resistance.