The administration of US President Joe Biden informed Congress on Monday of its planned sale of avionics software upgrades for Turkey's existing fleet of F-16 fighter jets, a deal anticipated to be worth up to $259 million.

The F-16 modernization package for the NATO member nation was first reported by Reuters after informal approval was given by leaders of the US congressional committees. It is worth noting that Turkey has also been awaiting a response to a proposal, opposed by Congress, to buy billions of dollars worth of F-16s from the US. If approved later, as part of the formal process, it would be the largest military sale to Turkey that Congress has authorized in years.

According to the US State Department's spokesperson, "Türkiye is a longstanding and valued NATO ally," and "The Biden Administration supports Türkiye’s efforts to bring the avionics of its F-16 fleet up to standard."

While Lockheed Martin Corp is set to become the primary contractor for the deal, it is maintained that the modernization package discussed by the Biden administration is separate from the proposed $20 billion sale of new Lockheed Martin F-16 fighters and nearly 80 modernization kits requested by Turkey earlier in 2021.

The smaller modernization package comes as a "positive signal" to Ankara following the latter's approval of Finland into NATO and the easing of tensions with Greece.

According to the spokesperson, the upgrade would boost interoperability between Turkish and NATO systems by upgrading communications, and provide enhancements to strengthen safety measures such as a ground collision avoidance system.

The permission does not guarantee that Congress will approve the larger transaction since US legislators are requesting that Turkey offer guarantees on topics unrelated to NATO expansionism. Among those requested guarantees would be putting an end to hostilities with Greece, forgoing the invasion of northern Syria, and imposing sanctions against Russia.

Such requirements are guaranteed to enrage Turkey, which has complained that Washington's behavior is unfair and that it has made "endless" demands in relation to the sale of F-16s.

'Positive outcome' anticipated ahead of F-16 jets purchase: Ankara

Turkish Foreign Minister Mevlut Cavusoglu said early on April 3rd that Ankara is expecting a "positive outcome concerning its bid to purchase F-16 fighter jets from the US, once Biden solves the remaining obstacles that lay ahead of the sale.

"In fact, there is no such thing as complete blocking. We know that the [Biden] administration is making sincere efforts. They are determined to provide Turkey with F-16 or kits required to modernize the existing Turkish aircraft. There are those who are against it in the Congress, but we know, that the administration is making effort regarding those who are against. We also expect positive outcome," Cavusoglu said, as quoted by Turkish broadcaster TRT Haber. 

The diplomat added that the Biden administration has to first convince the US Congress and get its approval to greenlight the deal, a deal he says can only be reached through dialogue with US lawmakers.

This comes right after reports published earlier in April revealed that Turkish President Recep Tayyip Erdogan slammed US Ambassador Jeffrey Flake for having met with opposition leader Kemal Kilicdaroglu, Erdogan's main opponent in the upcoming elections. 

"[US President] Joe Biden's ambassador visits Kemal. Shame on you, think with your head. You are an ambassador. Your interlocutor here is the president. How will you stand up after that and ask for a rendezvous with the president? Our doors are closed for him, he can no longer come in. Why? He needs to know his place," Erdogan said on Sunday, as quoted by the Turkish Star newspaper.

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