Texas Sen. Ted Cruz defended President-elect Donald Trump's phone conversation with Taiwan President Tsai Ing-wen on Twitter Saturday after Trump took heat for supposedly breaking with decades-old U.S. diplomatic policy for taking Ing-wen's call.

Critics claimed Friday that Trump violated a decades-old policy of "one China," where the U.S. forwent any official diplomatic relations with Taiwan. Others praised Trump for accepting the call.

Cruz was one of those who didn't see an issue with it. He wrote on Twitter that Trump's foreign policy decisions are already an "improvement" over those of President Barack Obama, who has infamously had diplomatic relations with Iran and communist Cuba during his presidency.

"I would much rather have Donald Trump talking to President Tsai than to Cuba's Raul Castro or Iran's Hasan Rouhani. This is an improvement," Cruz wrote on Twitter Saturday, taking aim at Obama's nuclear deal with Iran and his re-opening of diplomatic relations with Cuba.

Trump also took to Twitter late Friday to defend himself and the phone conversation.

"Interesting how the U.S. sells Taiwan billions of dollars of military equipment but I should not accept a congratulatory call," he wrote.

Following the election, Cruz and Trump have had a more amicable relationship than the one they had during the Republican primaries and following the GOP national convention this July. There have even been rumblings that Trump would consider Cruz for the open Supreme Court seat.