KABUL - The failure of Afghanistan to sign a bilateral security agreement (BSA) with the United States before the end of 2013, as demanded by Washington, has created uncertainties on the future of the insurgency-plagued country.

"I am not sure if the government forces will be able to prevent Taliban onslaught for regaining power if the US-led coalition forces leave Afghanistan," Abdul Karim, a middle-aged Afghan, said.

Like many Afghans, Karim expressed concerns that with the departure this year of the NATO's International Security Assistance Force (ISAF), majority of its members Americans, the United States would completely abandon Afghanistan without the BSA.

Washington has urged outgoing Afghan President Hamid Karzai to sign the agreement before the end of last year with a warning that failure to meet the deadline would mean that US forces would completely leave the country.

The signing by Kabul of the BSA before the yearend was endorsed by the 2,500 delegates to the traditional Loya Jirga or grand assembly of tribal elders and notables who met in November last year in the capital.

Despite last-ditch efforts by Washington officials to convince Karzai to sign the accord within the deadline, the Afghan president remained adamant, saying that Washington should first met some conditions that he set.

The conditions include a US halt to the search of Afghan houses during military operations, support for a meaningful dialogue with the Taliban, and ensure transparent elections, slated for April 5, 2014. These pre-conditions, however, have been rejected by Washington, who said it does not have the "magic wand" to satisfy these conditions overnight.

Amid ongoing standoff between Kabul and Washington, a US Senate delegation called on President Karzai here on Thursday, where they exchanged views on matters pertaining mutual interests including the controversial BSA.

"President Hamid Karzai met with Senator John McCain, Senator Lindsey Graham and Senator John Barrasso in Presidential Palace on Thursday," a statement released by Presidential Palace said.

The statement said during the meeting, Karzai reiterated his pre-conditions. "Afghans want to sign the BSA with the United States but they want to be assured that their demands are met and that the agreement brings peace and stability for their country," the statement said.

Under the BSA, Afghanistan would allow the United States to keep reportedly 8,000 to 12,000 troops to advice, train and assist the Afghan national security forces beyond 2014 in the war on terror.

"The government of Afghanistan, with the huge military and financial support from the United States, NATO and several more countries, has failed to wipe out the Taliban over the past 12 years," Karim said. "How could it be possible for the poorly- equipped Afghan security forces to annihilate the Taliban insurgency alone?"

The Taliban and other militants, apparently emboldened by standoff between Kabul and Washington, have intensified their attacks against government and civilian targets.

Five Afghan civilians were killed and 18 others were wounded on Thursday from a bomb attack by militants in Baraki Barak District in Logar province, just 60 kilometers south of Kabul.

The Taliban insurgents, who have been fighting Afghan forces and more than 84,000 NATO-led coalition troops, announced recently that they will continue their attacks against government and foreign soldiers, vowing there will be no pause in Taliban activities even during the harsh winter.

"Taliban's unchecked activities are a matter of concern for everyone. The attack in Logar is not the first and won't be the last one," Shafiullah, a Kabul resident, said.

He also predicted more Taliban attacks, saying "the Taliban were able to keep on their activities in the presence of US-led foreign troops and will certainly be able to launch more attacks to regain power in the absence of international forces."

The continued stalemate between Kabul and Washington over the BSA has also taken its toll on the economic activities of the country.

"Many businessmen have already shifted their businesses outside the country due to uncertainty about the future and many more will do the same if BSA is not inked," Khan Jan Alkozai, a businessman, said.

Because of the stalemate, Afghanistan's national currency Afghani has been tumbling against the US dollar. The exchange rate now is 56 Afghani to one US dollar from 52 Afghani to a dollar a month ago.