UNITED NATIONS — The U.N. Security Council voted Thursday to prevent the sale or shipment to Somalia of components of improvised explosive devices if there is "significant risk" they may be used to manufacture the often deadly devices that are increasingly being used in attacks by al-Shabab extremists.

It also urged the Somali government to keep cracking down on the militant group's illegal financing methods that U.N. experts estimate raised over $21 million last year.

The resolution, adopted by a 13-0 vote with Russia and China abstaining, reaffirmed the arms embargo on Somalia and banned the resale or transfer of any weapons or military equipment sold or supplied to help develop Somalia's National Security Forces and security sector.

Al-Qaida-linked al-Shabab remains the most active and resilient extremist group in Africa, controlling parts of southern and central Somalia and often targeting checkpoints and other high-profile areas in the capital, Mogadishu. It has fired several mortars this year at the heavily defended international airport, where the U.S. Embassy and other missions are located.

In their latest report, experts monitoring the arms embargo and other sanctions against Somalia said: "The threat posed by al-Shabab to peace, security and stability in Somalia goes beyond the impact of the group's conventional military action and asymmetric warfare to include sophisticated extortion and `taxation' systems, child recruitment practices and an effective propaganda machine."

The panel said al-Shabab raised more than the $21 million it spent last year on fighters, weapons and intelligence. Its investigation found the extremist group generated approximately $13 million in just four case studies -- a "taxation" checkpoint in Lower Juba, its extortion of businesses in Kismayo, two bank accounts associated with the group's collection of taxes on imports into the port in Mogadishu, and "zakat" -- an annual religious obligation.

The resolution adopted by the Security Council "notes with concern al-Shabab's ability to generate revenue and launder, store and transfer resources."

It calls on the Somali government "to continue working with Somali financial authorities, private sector financial institutions and the international community to identify, assess and mitigate money laundering and terrorist financing risks." It encouraged the government to consider a national identification program to help reduce the risks.

The council condemned al-Shabab attacks in Somalia and beyond, saying the group "continues to pose a serious threat to the peace, security and stability of Somalia and the region, particularly through its increased use of improvised explosive devices." It also expressed "grave concern" at the presence of affiliates linked to the Islamic State extremist group in Somalia.

The resolution demands that countries prevent the sale, supply or transfer of a list of components including explosive materials, explosive precursors, explosive-related equipment and related technology "if there is sufficient evidence to demonstrate that the item(s) will be used, or a significant risk they may be used, in the manufacture in Somalia of improvised explosive devices."

It requires any country supplying an item on the list to Somalia to notify the committee monitoring U.N. sanctions at least 15 days in advance with details and the purpose for the sale or transfer.

Russia's deputy U.N. ambassador, Anna Evstigneeva, noted that the amendments "meant to optimize the arms embargo" were made at the Somali government's request and expressed hope that "they will support normalization and reduce the terrorist threat coming, in the first place, from Al-Shabaab."

But she said Russia abstained because the resolution didn't take on board "our principled and duly substantiated proposals," including references to Djibouti and Eritrea, whose relations pose "no threat to international peace and security," and to human rights in Somalia, which should be dealt with by the Geneva-based Human Rights Council.

China's deputy U.N. ambassador, Dai Bing, said Beijing abstained because the council didn't accept its amendments calling for the council to explore benchmarks for assessing the lifting of the arms embargo on Somalia weren't accepted.

"The current embargo has been a serious impediment to enhance security capacity of the Somali government," he said. "The text fails to make a deep response to the strong desire of the Somali government to have the arms embargo lifted."

U.S. political coordinator Rodney Hunter welcomed the continuation of U.N. sanctions and the extension of the work of the panel of experts for another 12 months.

He said every council member has committed to uphold the arms embargo "in the interest of securing peace and stability both in Somalia, and in the broader region." To achieve that, Hunter said, the United States also supports "the increased focus on thwarting Al-Shabaab's exploitation of the financial system."