Japan's Prime Minister Shinzo Abe attends a meeting with Israel's President Reuven Rivlin (not pictured) at the president's residence in Jerusalem on Monday, Jan. 19, 2015. Abe cut short his Middle East trip after ISIS released a video on Tuesday, demanding a $200 million ransom for the release of two Japanese hostages. Reuters/Amir Cohen

New reports suggest that negotiations to secure the release of two Japanese hostages -- whose captivity was revealed only days ago -- have been in progress since as early as November, when Kenji Goto's wife initially received ransom emails, apparently from the Islamic State terrorist group. According to a report by the Japan Times, citing unnamed government sources, the wife of Goto, the freelance journalist featured in the most recent Islamic State hostage video along with Japanese businessman Haruna Yukawa, also received an email in December demanding a ransom of more than 2 billion yen (about $17 million), similar to the demands released Tuesday.

Tokyo sources revealed that Kenji Goto's wife and the Islamic State, also known as ISIS, had multiple email exchanges over the past few months, but the terrorists never explicitly threatened to kill Goto until now.

A video purportedly released by ISIS terrorists on Tuesday evening demands a ransom of $200 million within 72 hours soon after Japan announced non-military support to help combat the terrorist group. Japanese Prime Minister Shinzo Abe has publicly expressed concern over the short deadline, which forced him to cut short his trip to the Middle East, where he appealed for the assistance of local allies.

This information has led experts to believe that ISIS strategically timed the video of the two Japanese captives to correspond with Abe's announcement in Cairo Saturday of Japan’s $200 million in non-military assistance to countries fighting the terror group.

“They kept Yukawa and Goto locked up … waiting for Japan to announce their role in the fight against ISIS,” James Simpson, a Tokyo-based analyst, said in a separate report by the Japan Times. “They then issued a video on very short notice asking for more money than any government would be willing to pay. They win either way: Either Japan pays up and ISIS hits the jackpot, of they kill the hostages and spread their message of fear and terror to a new target.”

Abe has until Friday, Jan. 23, 2:50 p.m. Tokyo time to pay the $200 million.

“This is a very tough race against time, but the government will do its utmost,” Abe said to reporters after the hostage video was released. “I have ordered the government to use all diplomatic channels and routes possible … to ensure the release of the two people.”

Abe has also vowed that Japan will not be deterred from aiding to fight against ISIS. “We’ll coordinate with the international community from now on, and contribute more to the peace and prosperity of the region. This policy is unwavering and we won’t change this policy.”