Through its Twitter account, Samsung confirmed that the Exynos 5 Octa processor is indeed fully capable of connecting to an LTE network. The Korean giant's latest silicon supports all LTE bands.
(http://cdn.gsmarena.com/vv/newsimg/13/03/exynos-octa-lte/gsmarena_001.jpg)
This announcement essentially confirms that LTE connectivity was not a factor in Samsung's decision to offer the its Galaxy S4 (http://www.gsmarena.com/samsung_i9500_galaxy_s4-5125.php) flasghip with Qualcomm Snapdragon 600 and Exynos 5 Octa processor options. Instead, it is the latter's short supply, which leads to the current arrangement.
The LTE capability of the Samsung Exynos 5 Octa doesn't guarantee that every Samsung Galaxy S4 sporting the chipset will be capable of 4G connectivity. Samsung is yet to comment further on this matter.
Source (https://twitter.com/SamsungExynos/status/317337664078630912) | Via (http://www.sammobile.com/2013/03/28/samsung-exynos-confimed-lte-exynos-5-octa/#.UVSOhPpL3P4.twitter)
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