U.S. Defense Secretary Jim Mattis, during his day-long visit to Kabul on Monday, also warned "2017's going to be another tough year for the valiant Afghan security forces and the global troops".
Mattis, the first member of U.S. President Donald Trump's cabinet to visit the country, was meeting with officials of the U.S.'s joint mission with NATO Operation Resolute Support, as well as Afghan government and security officials, including President Ashraf Ghani.
Nicholson's also urged Congress to send more USA troops to Afghanistan, where it's held a military presence since 2001.
At a news conference with Defence Secretary Jim Mattis at his side, Gen. John Nicholson, the American commander in Afghanistan, wouldn't provide specifics about Russia's role in Afghanistan.
Moscow believes it is necessary that the Taliban engages in dialogue with Kabul to achieve peace in Afghanistan, Lavrov said, adding that the group must "stop violence, cut ties with terrorism, respect the constitution". "But we're going to have to confront Russian Federation where what they're doing is contrary to global law or denying the sovereignty of other countries".
The Taliban now control about 40 percent of the country.
In an official statement, the Afghan Presidential Palace said President Mohammad Ashraf Ghani met the USA secretary '"ahead of expected decision on more US troops for Afghanistan".
As many as 140 Afghan soldiers were killed by Taliban insurgents disguised in army uniforms in what could be the deadliest attack ever on a military base in the country.
As part of the administration's review of Afghan policy, Mr Trump's national security adviser, Army Lt Gen HR McMaster, visited Kabul last week to consult with Gen Nicholson and with Afghan officials.
"Any weapons being funnelled here from a foreign country would be a violation of worldwide law", he said. The attack has led to several resignations within the Afghan military.
A senior American military official in Kabul said Monday that it appears likely the attack was either carried out by or planned by a Pakistan-based Taliban faction known as the Haqqani network, which is a US government-designated terrorist organization.
The Taliban also claimed responsibility for another attack Monday at Camp Chapman, a base that houses Central Intelligence Agency and USA special operations forces.
"The Taliban has gained increasing power over the years while the United States has moved towards its 16th year being in war in Afghanistan". There is no word if Nicholson's request for more US troops will be granted.