Joachim Low's Germany side cruised to a 3-0 victory over Austria in Munich on Friday thanks to goals from Miroslav Klose, Toni Kroos and Thomas Muller.
Victory, which saw Klose draw level with Gerd Muller as Germany's all-time scorer on 68 goals, moves Germany five points clear at the top of Group C with three games to go. Sweden will provide the toughest competition to Germany after they beat the Republic of Ireland 2-1 in Dublin to move into second place.
Italy's 1-0 win over second-place Bulgaria opened up a seven-point lead in Group B. Should Italy match or better Bulgaria's result in Malta on Tuesday, they will qualify for Brazil.
Alberto Gilardino's 38th-minute strike was enough to seal the win for Cesare Prandelli's side in Palermo as they look to qualify for their 18th World Cup.
Belgium moved five points clear at the top of Group A with a 2-0 victory over Scotland at Hampden Park, Steven Defour scoring the opening goal in the first half before Kevin Mirallas sealed the win in the closing minutes.
They are the brink of qualification after Serbia held Croatia to a 1-1 draw in Belgrade. Igor Stimac's side had taken the lead through Mario Mandzukic but Aleksandar Mitrovic levelled the score.
The Netherlands remain on course for the finals after a controversial late Robin van Persie penalty earned them a 2-2 draw against Estonia.
Louis van Gaal's side are six points clear of Romania in Group D, but were lucky to snatch a point after Konstantin Vassiljev had struck twice to put the home side on the verge of an historic victory.
Group E leaders Switzerland were stunned at home to Iceland as they saw a 4-1 lead disappear in Bern to draw 4-4.
Johann Berg Gudmundsson scored a hat-trick for the visitors – including a 91st-minute equaliser – to keep Iceland in contention for a play-off place.
Portugal found themselves 2-1 down seven minutes into the second half against Northern Ireland, but Cristiano Ronaldo rescued his side with a 15-minute hat-trick as they secured a 4-2 win.
They move two points clear in Group F of Russia, who had a comfortable 3-0 win over neighbours Hungary.
England sit on top of Group H thanks to a 4-0 win over Moldova at Wembley, Steven Gerrard, Rickie Lambert and a double from Danny Welbeck secured the win for Roy Hodgson's side.
World and European champions Spain took advantage of France's 0-0 draw with Georgia to open up a three-point lead at the top of Group I.
Jordi Alba and Alvaro Negredo wrapped up the victory for Vicente Del Bosque's side in Helsinki, and with two games to go, they look on course to defend their title in Brazil.
Group G leaders Bosnia lost 1-0 against Slovakia and Greece beat Liechtenstein 1-0 to move level on 16 points with three games to play.
Elsewhere on Friday, Wales fell to their fifth defeat of the campaign after Aleksandar Trajkovski secured Macedonia a 2-1 win.
Czech Republic fell to a surprising 2-1 defeat at home to Armenia in Group B that has opened up the race for second place in the group. Armenia moved level on points thanks to goals from Karlen Mkrtchyan and Gevorg Ghazaryan.
Denmark are also on nine points from seven matches after they recorded a 2-1 win over Malta.
Plenty of goals flew in around Europe as some of the minnows fell to heavy defeats. Ukraine thrashed San Marino 9-0, while Turkey beat Andorra 5-0 and Russia securing a 4-1 win over Luxembourg.
Kazakhstan notched up their first win of the campaign with a 2-1 victory over the Faroe Islands, while in Group E, Norway and Slovenia both recorded victories to maintain their battle for second place.
In Oslo, Norway beat Cyprus 2-0, while Slovenia held off the challenge of Albania to win 1-0 in Ljubljana.
Latvia also recorded a victory as they beat local rivals Lithuania 2-1 in Group G, while Poland held Montenegro 1-1 to a draw in Warsaw thanks to Robert Lewandowski's equaliser.
