Joint Chiefs Chairman Gen. Joseph Dunford arrived in Afghanistan on Monday for a final assessment on whether to boost U.S. troop levels to counter a nationwide Taliban offensive and increasing terror attacks by the ISIS offshoot called Islamic State-Khorasan Province, or IS-K.

Dunford's report on the deteriorating security situation will weigh heavily in Defense Secretary Jim Mattis' decision, expected next month, on the long-standing request of Army Gen. John Nicholson, commander of U.S. Forces-Afghanistan and NATO and coalition troops, for an increase of 3,000 to 5,000 troops in the Force Management Level.

In House and Senate hearings last week, Mattis said President Donald Trump had given him authority to set the force level in Afghanistan, which now stands at about 8,400 troops. However, the SecDef said a "little under 10,000" are now in Afghanistan, possibly because of overlaps in regular troop rotations. Trump had already granted Mattis similar authority to set troop levels in Iraq and Syria.

NATO and coalition troops have about 5,000 troops in Afghanistan, and Mattis has signaled that he expects more commitment from allies, either with troops or funding.

Mattis also told Congress that he will present a revised regional strategy, in coordination with Secretary of State Rex Tillerson, to Trump in mid-July. In doing so, he disputed published reports that he had already signed off on sending 4,000 more U.S. troops into the nearly 16-year-old conflict in Afghanistan.

Dunford's visit to Kabul coincided with the regional tour of Chinese Foreign Minister Wang Yi, who was in Kabul on Saturday and met with Pakistani leaders Sunday.

Wang's visit followed on agreements earlier this month between Afghan President Ashraf Ghani and Chinese President Xi Jinping on regional cooperation and China's support for peace talks with the Taliban, which Taliban leaders have rejected while U.S. troops remain in the country.

Afghanistan's TOLOnews quoted Wang as saying in Pakistan, "Both Pakistan and Afghanistan have expressed the interest that China should play a certain role, and that is the indicator of the high level of interest both countries have placed in China. China of course is ready to play a constructive role in political relations."