Key summit set for April 24 in Riga.

From the FT:
"Greece is preparing to take the dramatic step of declaring a debt default unless it can reach a deal with its international creditors by the end of April, according to people briefed on the radical leftist government's thinking."

The default wouldn't technically take place until at least June 1. The report said they will default on $2.5 billion in IMF loans starting with payments due May 1; the IMF has a 30-day grace period.

The story says it could be a negotiating tactic buy Tsipras is walking a fine line.