PARIS (REUTERS) - The foreign ministers of Ukraine, Russia, France and Germany agreed on Tuesday to seek a reinforcement of the international monitoring mission in Ukraine and renewed their calls for an oft-breached ceasefire agreement to be respected.

The meeting of around three hours in Paris was called in a bid to rescue an agreement the four powers brokered this month in Belarus capital Minsk, setting out terms for a ceasefire and the withdrawal of arms in the conflict in east Ukraine between government forces and pro-Russian rebels.

"Against this backdrop we must be more ambitious in how we implement individual steps of the Minsk Agreement," Germany's Frank-Walter Steinmeier told reporters after the meeting, calling the lack of confidence between the two sides "total".

Steinmeier said the four had agreed to call for a one-year extension to the mandate of Organisation for Security and Co-operation in Europe (OSCE) ceasefire monitors in Ukraine and reinforce their personnel, equipment and funding.

He noted there had been some signs of progress regarding agreements to withdraw heavy weaponry from conflict zones but said that should now physically take place "within the coming days".

Russian Foreign Minister Sergei Lavrov left the talks saying they were useful.

His Ukrainian counterpart Pavlo Klimkin was more downbeat, noting the four had not agreed language condemning events on the ground in Debaltseve, a town taken by pro-Russian rebels since the ceasefire was due to start.