ISLAMABAD — Additional F-16s from the US remain central to Pakistan's modernization efforts, but analysts say since there could be hurdles ahead, surplus fighters may be a credible alternative.

News reports here citing senior officials have stated that the air force requires some 190 new aircraft to replace its legacy Mirage III/5 and Chengdu F-7 fighter fleets by 2020. Some of this figure will be made up of JF-17 Thunder Block III aircraft which air force officials have stated will feature a leap in capabilities over the current aircraft in service.

However, there is no expectation that current JF-17 production will be ramped up in either Pakistan or China — or perhaps both — to meet this need, and further F-16s are being sought, hence the recent deal for eight F-16 Block 52 fighters.

This deal is almost finalized, and Pakistan appears to be placing faith in Lockheed Martin's need to keep the F-16 line running with new orders to help it acquire another ten F-16s that it had initially hoped to acquire with the recently cleared aircraft.

Claude Rakisits, senior fellow at Georgetown University's School of Foreign Service and an expert on Pakistani affairs, is optimistic.

"Given that the Obama administration recently managed to have Congress approve the sale of eight F-16s to Pakistan, logically the sale of an additional 10 F-16s shouldn't be a real issue for Congress," he said. "Also, given the constructive nature of the ministerial-level US-Pakistan Strategic Dialogue, which was held in Washington recently, objective indications are that convincing Congress should not be too difficult."

However, the recent admission by Pakistan's adviser to the prime minister on foreign affairs, Sartaj Aziz, at a meeting hosted by the Council on Foreign Relations that Pakistan had provided "various degrees of support to the Taliban since 2001" may prove counterproductive.

"While everyone in Washington suspected that was the case, the fact that Aziz admitted this quite casually and publicly as if there was nothing to it may well have damaged Pakistan's chances of getting those additional fighter jets," Rakisits said. "Wavering US senators may not be so keen to sell such sophisticated hardware to a country which has openly admitted providing assistance and refuge to the Taliban despite denying doing so since 2001. So in light of Sartaj Aziz's admission, Pakistan may well have to look elsewhere to modernize its air force."

Pakistani officials have noted French and Russian aircraft as alternatives, though the former are admitted by them to be expensive, and little appears to have come of reported talks for Russia's Su-35 Flanker.

Rakisits also cites China as an alternative source.

Pakistan had planned to acquire an advanced variant of the Chengdu J-10 Firebird, but this plan appears to have been ditched. Pakistan has subsequently been linked to the stealthy Shenyang J-31/F-60, but there is no official confirmation of plans.

Given it is still in development, the J-31 is not applicable to the current time frame requirement.

Analyst, author and former air force pilot Kaiser Tufail said Pakistan does not have many options.

"There has been talk of 10 more F-16C/D-52 to add to the eight approved a few days ago. That should complete one more squadron of this latest version," he said. "We have the infrastructure to simply add aircraft into the system, something that would not be so easily doable in case of Russian or Chinese systems.

"Switching to a small number of Russian and Chinese aircraft would not be a good idea from the point of view of maintainability, as it would entail major investments in new back shops, test benches and many more maintenance facilities."

Even though Pakistan's economy is recovering from economic mayhem wrought by the previous government and its foreign currency reserves are approaching $20 billion, such an investment is unrealistic.

Tufail, however, said there is still a credible alternative to additional F-16s.

"Surplus F-16A/B-MLU from European countries are the best option, and other than range, they do not differ majorly from the Blk-52s. I think they will serve our requirements very well, particularly as we have big numbers to fill in," he said.

Pakistan hopes to maintain a combat force of 350-400 aircraft, and the F-16 clearly plays a large role in this endeavor even though up to 250 may eventually be JF-17 variants. In this regard, Tufail said Washington is in a very advantageous position vis-à-vis its relationship with Islamabad.

"The fact that the Americans can use the F-16s and such hardware for political leverage must not be lost on us, unless we are ready for a complete break. That would be suicidal, as much of the high-tech element of the [Pakistan Air Force] is sourced from the USA," he said.

Nevertheless, he remains optimistic.

"The danger of sanctions is and has always been there, but things do not seem that bad as far as [Pakistan]-US relations are concerned."

Rakistis, however, said despite Washington’s clearly advantageous position, the potential spoiling party may not be Pakistan, but Congress, which could start flexing its muscles over the additional 10 F-16s.

"One shouldn't forget that while the sale of the eight F-16s has pretty much been finalized, it's not as if it was plain sailing getting it through Congress. This additional request may be going a bridge too far for some senators, especially in this highly charged election year," he said.