JERUSALEM, Jan. 24 (JTA) — It may well have been a case of doing it to the other person before the other does it to you. This was the rationale some observers attributed to Prime Minister Benjamin Netanyahu, who fired Defense Minister Yitzhak Mordechai on Saturday night and offered the post to his former political mentor, Moshe Arens. Seen as something of a pre-emptive strike, Netanyahu’s decision to dismiss Mordechai came amid mounting speculation that the popular former general would take over the leadership of a new centrist party and square off against Netanyahu in the May vote for prime minister. According to this scenario, Netanyahu spared himself the embarrassment of receiving the resignation of the person who tops recent polls as the premier’s most popular Cabinet minister — and perhaps the most politically moderate. Arens, on the other hand, is a political hawk who is challenging Netanyahu for the leadership of Likud. He said he would wait till after Likud’s primary Monday to accept the premier’s offer. Mordechai fueled speculation that he was poised to leave Netanyahu’s government by failing to register by last Friday’s deadline for the Likud Party primary. This may have been the final straw for Netanyahu, who in recent weeks urged his defense minister not to bolt Likud — as Mordechai held a series of highly publicized talks with members of the still-forming centrist party. At a news conference Saturday night, Netanyahu delivered the opening blow in what is expected to be a no-holds-barred political fight, accusing Mordechai of holding simultaneous negotiations with Likud and the centrists in order to secure his political future. “In recent weeks and days, I witnessed that your personal ambition supersedes any other consideration,” Netanyahu said, reading a letter that was delivered to Mordechai’s house outside Jerusalem minutes before. Mordechai, who was meeting with centrist politicians when the letter was delivered Saturday night, came out swinging. “This is a letter full of lies, smears and inaccuracies, which are fitting a petty politician,” the ousted defense minister told reporters. Nor did the rhetoric did get any milder by Sunday. Mordechai “organized a conspiracy to topple the government in which he was serving,” the premier told Israel Radio on Sunday. A relative moderate among Netanyahu’s minister’s, Mordechai had some harsh words of his own when he attended his final Cabinet session Sunday. Donning a yarmulka, he read a verse from the Book of Psalms as a way of delivering his message that Netanyahu is a liar and an enemy of peace. “Deliver my soul, O Lord, from lying lips and a deceitful tongue,” the secular ex-general intoned, citing Psalm 120. “My soul hath long dwelt with him that hateth peace. I am for peace, but when I speak, they are for war.” He later went to the Western Wall, where, again putting on a yarmulka, he read the same verses. Mordechai, who is of Kurdish ancestry, appeals to Sephardi voters, a traditional source of Likud support. He entered politics just before the 1996 elections, following a military career in which he held army commands along the Lebanese border, in the West Bank and in the Gaza Strip. He was slated to hold a joint news conference with other leaders of the centrist party Monday night, once his dismissal went into effect, to announce their campaign strategy. It remains unclear whether the centrist grouping — which includes former army chief Amnon Lipkin-Shahak, former Likud Finance Minister Dan Meridor and former Tel Aviv Mayor Roni Milo — will have enough political clout to defeat Netanyahu. Mordechai has refrained from commenting on whether he will lead the centrists. But Milo, a former Likudnik who helped found the party, said polls indicate that Mordechai has the best chance of all of them to beat Netanyahu in May.