Nigeria ? The front-runner in Nigeria’s upcoming presidential election underwent medical treatment in Germany on Wednesday, saying he had experienced breathlessness, his spokesman and the British Broadcasting Corp. said.

Katsina Governor Umaru Yar’Adua, the ruling party’s candidate in the April vote, flew overnight to an undisclosed medical facility in Germany and was in stable condition, said his spokesman, Ndu Ughamadu. “I spoke with him myself by telephone one hour ago,” Ughamadu said. “He’s very stable.”

He didn’t give details on the candidate’s ailment or treatment.

In a statement, Yar’Adua promised to return home soon and rejoin the campaign trail.

“I wish to thank all my supporters for their well wishes, and want to assure them I’m quite fine and will be back on the campaign trail shortly,” he said.

The BBC reported that it was able to speak to Yar’Adua by phone, and quoted him as saying he had suffered from breathlessness and sought a medical checkup abroad on his doctor’s advice.