Expressing concern over China's military build-up, the head of US intelligence said Chinese construction activities at its outposts in the disputed South China Sea will continue to spark regional tension.

"China's leaders are pursuing an active foreign policy while dealing with much slower economic growth. Chinese leaders have also embarked on the ambitious military reforms in China's history," James Clapper, director of national intelligence said in his testimony before Senate Armed Services Committee on Tuesday.

"Regional tension will continue as China pursues construction at its expanded outposts in the South China Sea and because competing claimants might pursue actions that perceive as infringing on their sovereignty," he said.

Agreed, the Defence Intelligence Agency Director Vincent Stewart. "China is pursuing a long-term, comprehensive military modernisation program designed to improve its capability to fight short-duration, high-intensity regional conflicts."



"While preparing for a Taiwan contingency remains the primary driver of the People's Liberation Army (PLA) modernisation, the Chinese military has increased its preparations for other contingencies, including conflicts in the East or South China Seas," he added.

Stewart said the Chinese Army is modernising its nuclear forces by enhancing silo and underground facility-based inter-continental ballistic missiles and adding more road-mobile systems.

In addition, the Chinese Navy deployed the JIN-class nuclear-powered ballistic missile submarine in 2015, which, when armed with the JL-2 SLBM, provides Beijing its first sea-based nuclear deterrent, he said.

Senator John McCain, chairman of the Senate Armed Services Committee, said China continues its rapid military modernisation while taking coercive actions to assert expansive territorial claims.

Observing that China will continue to incrementally increase its global presence, Clapper said mileposts have included symbolic and substantive developments, such as the Monetary Fund's decision in November 2016 to incorporate the renminbi into its Special Drawing Rights currency basket and China's opening of the Asian Infrastructure Investment Bank in early 2016.

Amid new economic challenges, Chinese leaders are pursuing an ambitious agenda of economic, legal and military reforms aimed at bolstering the country's long-term economic growth potential, improving government efficiency and accountability, and strengthening the control of the Communist Party, he said.

The scope and scale of the reform agenda-coupled with an ongoing anti-corruption campaign-might increase the potential for internal friction within China's ruling Communist Party.

Additionally, China's leaders, who have declared slower economic growth to be the "new normal" will nonetheless face pressure to stabilise growth at levels that still support strong job creation, Clapper said.

On Afghanistan, Clapper said the war-torn country is at serious risk of a political breakdown this year. "Afghanistan is at serious risk of a political breakdown during 2016, occasioned by mounting political economic and security challenges," Clapper said.

"Waning political cohesion, increasingly assertive local power brokers, financial shortfalls and sustained countrywide Taliban attacks are eroding stability," he said as several top American senators expressed their concern over the current situation in Afghanistan.

Stewart said the Afghan security forces are still struggling. "In their first full year in the lead, Afghan security forces increasingly conducted independent operations. However, these forces struggled to adapt to a lack of coalition enablers and a high operational tempo, which led to uneven execution of operations," he said.

"As a result, insurgents expanded their influence in rural areas, limiting the extension of government control. The deployment of Afghan specialised units and their enablers will be necessary to continue secure in key population centers," Stewart said.

McCain said in Afghanistan the security and political environments both remain challenging.

"The Taliban have sought to take advantage of the still maturing Afghan security forces by increasing their operational tempo, especially in rural areas," he said.

On Bangladesh, Clapper said the bitter fight between the two major political parties in the country is giving space for the growth of terrorist organisations including ISIS.

"Prime Minister Sheikh Hasina's continuing efforts to undermine the political opposition in Bangladesh will probably provide openings for transnational terrorist groups to expand their presence in the country," Clapper said.

"Hasina and other government officials have insisted publically that the killings of foreigners are the work of the Bangladesh Nationalist Party and the Bangladesh Jamaat-e Islami political parties and are intended to discredit the government," he said.

"However, ISIS claimed responsibility for 11 high-profile attacks on foreigners and religious minorities," he added.