Sen. Ted Cruz on Thursday called out Donald Trump for previously supporting immigration amnesty in 2013, back when Cruz was fighting against the Gang of Eight amnesty bill.

"Congress must protect our borders first. Amnesty should be done only if the order is secure and illegal immigration has stopped," Trump tweeted in August 2013, expressing a more lenient stance on immigration than he does on the campaign trail today.

"Trump SUPPORTS amnesty. Read his 2013 tweet — while I was leading the fight to defeat Rubio Gang of 8 amnesty. #Truth" Cruz said in his retweet of Trump's words.

Trump SUPPORTS amnesty. Read his 2013 tweet--while I was leading the fight to defeat Rubio Gang of 8 amnesty. #Truth https://t.co/AMVoRb0xob — Ted Cruz (@tedcruz) January 21, 2016

Both Trump and Cruz have gained significant support amongst evangelical and conservative voters in Iowa due to their firm stances on halting illegal immigration. With less than two weeks until the Iowa caucus, Cruz and Trump are virtually tied in the state, and Cruz trails Trump by just 1.5 percent in an average of polls. Cruz leads Trump in the Washington Examiner's presidential power rankings.

Cruz, a longtime opponent of immigration reform in the Senate and on the campaign trail, has often called out Trump for being new to his conservative views of immigration. Since launching his primary campaign, Trump has vowed to build a wall between Mexico and the United States to keep out "rapists" and criminals if elected.