Significant increase in the Haqqani network activity in Khost, Paktia, Logar and Wardak has been reported which are on infiltration routes from Pakistan to launch attacks against the Afghan capital, CNN reported quoting top NATO officials in Kabul.
"Whether or not NATO and US will have to provide more assistance to the Afghan forces along the border with Pakistan," the officials said would depend on "the level of threat coming out of Miranshah".
General John Allen, the commander of US and NATO forces in Afghanistan, has completed a 90-day assessment of the campaign plan and suggested a gradual shift of focus to pulverise Haqqani network militants in the east.
"As things improve in the south, we will focus more on the east," officials said.
Though US officials have given bare details about the build-up to launch the new operation against the Haqqani terror network, Pakistani media reports have said that heavy artillery, fresh troops and helicopter gunships have been moved closer to the border to hit Haqqani terror network's stronghold in the region.
The new Afghan operation in the east against the Haqqani militants comes as Pentagon said that cross-border attacks emanating from Pakistan against US-led forces in Afghanistan have increased since the US raid that killed Osama bin Laden in Pakistan.