AS concern grows in Pakistan about the fallout of the deteriorating security situation in Afghanistan, protracted fighting that morphs into a civil war will pose severe dilemmas and multiple challenges for the country. Prime Minister Imran Khan reiterated this fear in a recent interview with an American TV network when he said such an outcome would be the `worst-case scenario for the country`.

Pakistan`s security is inextricably tied to Afghanistan. Prolonged strife in its neighbour will expose Pakistan to security threats that it has dealt with in the past at a heavy costin lives and social and economic consequences. For over four decades Pakistan has borne the brunt of war, foreign military interventions and conflict in Afghanistan that produced grave repercussions for the country`s security, stability and economic development. The destabilising ramifications are too well known to bear repetition here. More turmoil on its western frontier would mean the country will have to simultaneously deal with internal, regional and international challenges that would flow from this outcome.

In a back-to-the-future scenario Pakistan will be faced with a serious threat to its stability if civil war erupts in Afghanistan and spills over into its border areas. Pakistan has sought to mitigate this danger by fencing much of the border, sealing illegal crossing points, increasing border posts, strengthening the capacity of the Frontier Corps, upgrading training of law-enforcement personnel, enhancing technical surveillance and stationing regular troops there. While these measures are necessary, they may not be sufficient to stop the determined from crossing over given the long border and the mountainous terrain and topography.

Moreover, a chaotic situation across the border will provide fertile ground and more space to a host of militant groups to continue operating from there.

The principal but not only threat is from the TTP (the Pakistani Taliban) whose 6,500 members are based in Afghanistan and launch cross-border attacks from there. A reunified TTP has reinforced its capacity. The latest report of the UN`s sanctions monitoring team notes that `the return of splintergroups to the TTP fold has increased its strength`.

The TTP`s links continue with the Afghan Taliban, which are acknowledged by Pakistan`s security of ficials. TTP leader Noor Wali Mehsud surfaced recently to announce in a CNN interview that his militant group will continue its `war against Pakistan`s security forces` and its aim is to `take control of the border regions and make them independent`.

A surge in violence in North and South Waziristan has led to rising casualties among Pakistani security personnel in recent months. Since May, there have been 167 terrorist incidents in KP and Balochistan, an ominous portent of what could lie ahead. Armed groups residing in Afghanistan would pose a threat to Pakistan with some making common cause with elements who were defeated but dispersed after a series of successful operations by security forces.

The UN report says that `a significant part of the Al Qaeda leadership is based along the AfghanistanPakistan border` while ISIS-K or Daesh `remains active and dangerous`.

Pakistani military officials have already warned of terrorist sleeper cells being galvanised if there is protracted fighting next door. In Balochistan there could be a further rise in violent activity by revived dissident and other groups orchestrated by hostile foreign intelligence agencies. Thus, Pakistan`s hardwon gainsinits counterterrorism campaign could be upended. The prime minister said pointedly in the PBS interview that a civil war in Afghanistan would mean `terrorism in Pakistan`. Also, forces of extremism in the country will take heart and be emboldened by the Taliban`s military success.

A civil war could also lead to a fresh refugee influx into Pakistan which has hosted three million Afghan refugees for decades now. Pakistani of ficials worry that fighting will force more Afghans to flee with estimates of new refugees ranging from 500,000 to 700,000. Apart from instituting more ef fective border controls the government is working on a plan to establish camps near the border to prevent refugees from entering the mainland. Whether the Iranian `model` can work here is open to question especially as tribes are so intertwined on bothsides of the border. Using the nomenclature `externally displaced Afghans` to describe them could put at risk international assistance for these refugees as that depends on their refugee status. World Bank funding for refugees too could be in jeopardy.

Then there is the likely economic fallout that Pakistan also experienced in the past. Given how fragile and vulnerable the economy is the shock from a civil war next door and threat of violence at home will jeopardise prospects of growth and investment. This will place Pakistan in a zone of instability which will dampen trade and investment badly needed to achieve economic growth targets.

The recent past shows that Pakistan had to bear billions of dollars in economic losses in the aftermath of 9/11 when the `war on terror` spilled over into the country`s border areas and cities.

Beyond this, a civil war can lead to a regional proxy war, as it did in the past, but with more damaging consequences and drawing in more countries that perceive threats to their security and are already beefing up their defences. It could turn out to be fiercer than what followed the Russian military withdrawalin the 1990s as neighbours and near neighbours act to protect their interests. More regional states have security concerns now than was the case during Afghanistan`s previous bout of civil war because of transnational armed groups and foreign terrorist fighters who operate from there. They include ETIM, Daesh, IMU, TTP and of course Al Qaeda. There are also fears of fighters in Syria relocating to the region. A proxy war could trigger a regional geopolitical crisis of uncertain proportions.

All this may sound alarmist but it is predicated on a worst-case scenario of Afghanistan descending into chaos and civil war. This only underlines the urgency of regional and international diplomatic efforts to avert such an outcome. There is time yet for these ef forts to make headway. Ultimately however, it will be up to the Afghan parties to make the dif ficult compromises that can deliver peace to their long-suffering people.• The wifter is a former ambassador to the US, UK & UN.